Apprehension is the enemy of interface design 15 Aug 2005

35 comments Latest by John

Go to your local grocery story or Home Depot, or whoever else has self checkout and just watch. Watch for about 10 minutes. You’ll see the physical manifestation of apprehension caused by people interacting with machine-based interfaces.

You’ll see lots of squinting, lots of “almost pushed” buttons, lots of hand sliding and gliding (when someone moves their hand around the screen seeking out the button the want to press), lots of slow motion (“the slower I go the less mistakes I can make”), lots of corner-eye looks to see what everyone else is doing, and lots of quick pull aways. It’s as if the faster you pull your hand away from the screen the less likely the machine will think you meant to do something wrong.

Apprehension is the enemy of interface design. Like Krug says, Don’t Make Me Think. Any thinking also includes a thought about trying something different, the opportunity cost of pressing this over that, and, worst of all, the thought of bail out.

When designing interfaces try to imagine all the things that would scare someone away from a choice. The language, the shape, the color, the proximity, the weight, the position. Even things as seemingly simple as save or submit can cause enough confusion to let apprehension slip in.

And, finally, don’t forget about what happens after someone fills out a form, presses a button, or clicks a link. As an interface designer your job doesn’t end in helping someone make a decision — it follows through to the result of the decision itself. Did it work? Did it not? What just happened? What happens next? Put simply, your interface needs to answer more questions than it asks.

35 comments so far (Jump to latest)

Dan Boland 15 Aug 05

LOL, I have a love-hate relationship with the self-checkout aisle of the grocery store. I love it because I don’t have to talk to anyone, i.e. a surly cashier that doesn’t want to be there in the first place. I hate it because half the time they don’t fucking work. (Come on, how many times have you gotten the “unexpected item in bagging area” error? It’s enough to drive someone mad.)

I’ve also seen people do all of the things you just described, Jason. And I think part of it has to do with the fact that, as I just mentioned, they haven’t exactly worked out all the kinks in the software. But most of all, it’s because the interface is a little frightening to someone who’s never used it, mainly because it doesn’t give you a clue as to how it works, beyond the “pick a language or start scanning” prompt.

For instance, I convinced a friend of mine to use the self-checkout aisle, and he started scanning everything way too fast. So, of course, the machine kept yelling at him. He got annoyed.

I think a good rule of thumb is “design for your mom.” I’m willing to bet that most of our moms aren’t very savvy when it comes to technology. So if your mom gets it, you’re probably on the right track. A variation could be “design for the stupidest person you know.” And you’re right, Jason, I think most people don’t use the self-checkout because it’s too much trouble. But it doesn’t have to be.

Brady Joslin 15 Aug 05

I’ve always thought those who claim they are not savvy computer users are actually just unconfident computer users. Savvy users may be equally uncertain of what the UI designer is attempting to communicate, but they are not afraid to tinker and try interacting with the computer. Trial and error is a huge part of becoming an advanced user of any system. Reducing apprehension enhances confidence.

The other interesting point here is some machines and systems seem generally more aligned to certain individual’s conceptual models. I’m great with computers, but you would never ask me to fix your car. For some reason, I feel apprehension when even changing engine oil, but I’ll rip a computer system apart and put it together with relative confidence.

As always, don’t forget the type of users you are interacting with. Ideally, you would create an agile interface that can alter itself to match their needs to reduce apprehension.

Dan Boland 15 Aug 05

Brady: I always thought that kind of action was inferred in the phrase “savvy users,” but that’s an excellent way of explaining it. I might have to plagiarize you in the future. =)

As always, don�t forget the type of users you are interacting with.

Yeah, that’s why I don’t understand why the self-checkout machines aren’t better. Everyone I know goes to a grocery store, so the average type of user is anyone. There are so many unnecessary features in the software, like the animations, the dorky sound effects, the “human” voice. It all slows everything down.

Joseph Wain 15 Aug 05

Glad to know I’m not the only one who “dislikes self-checkout lines”:http://www.penandthink.com/niggle/archive/000109.html and “those card reader”:http://www.penandthink.com/niggle/archive/000115.html things.

Apprehension really is the right word, too. I’m constantly concerned that machine is going to beep or freeze or for some reason require human assistance from a (grumpy) clerk.

As an aside, this comment-posting form has a “post” button but no “preview’. Does it accept Textile or basic HTML or what? I don’t think I can edit my comment later so it’d be nice to have a “basic markup OK” note at least :)

Douglas Livingstone 15 Aug 05

There are so many unnecessary features in the software, like the animations, the dorky sound effects, the �human� voice. It all slows everything down.

Simplicity by adding more features!

Joseph Wain 15 Aug 05

Ah! It does say “HTML is allowed” and I totally missed it. Sorry! Enjoy my mangled Textile syntax.

Dan Boland 15 Aug 05

Joseph: The “what line am I in?” question is another big problem with the overall setup… I mean, isn’t someone familiar with the concept of queueing?

Howard Mann 15 Aug 05

Great points and oh so true.

It reminded me of a conversation I had with a UPS driver over the ease of use of the highly sophisticated “tablets” that they each carry with them for tracking, electronic signatures, pick up, dispatch, routing, etc….

When I asked him if it was hard to learn and use he showed me the instructions flashing on a screen that was situated just above 4 large blue directional buttons. The screen said simply: “PRESS THE BLUE UP.”

One choice and one simple direction. Makes it hard to be unsure and easy to be confident in your action.

Caleb 15 Aug 05

Having never used a self checkout I can’t comment from experience as to the difficulty with using them. I trust though that they are very frustrating.

However — what are self checkout machines trying to solve? Better customer experience? Dan mentions a distaste for “surly cashier[s] that [don’t] want to be there in the first place” — is this the best solution?

In terms of Experience Design is even a good checkout machine > any human?

Roger’s Video (a Canadian video store) has on all their doors “The Experience Starts Here.” In the case of the one around the corner from my old apartment the experience started with the smell of moldy carpet.

Would it have been better to finish that off with an android or a human saying thanks?

Dave Simon 15 Aug 05

Totally agree about those self-checkout things. They suck. I’m a total geek and I get apprehensive about using them. If I have a single item in my cart that doesn’t have a bar-code (like vegetables sold by weight) I skip it and go to a real person.

The best version I’ve ever used was the one they were experimenting with at my local Costco. You took a bar-code scanning gun with you shopping, scanning items as you shopped. When you got done, you plugged the gun in, it downloaded what you had in your cart, and you were done.

It didn’t rely on weight to make sure you weren’t taking anything, so it wasn’t as “secure” - but Costco always relies on the door “greeter” to check that anyway.

The voice is the most annoying part for me. Make a certain sound when I scan an item right, make a different one if there is an error. Put the error on screen. I don’t need it to read off the prices.

I was buying 10 of the same item the other day. Every one I scanned said, “One twenty-five, twenty-five cents savings.” (The items cost $1 each, not the $1.25 that it might imply, normal cost $1.50.) I was scanning them fast enough that when I was done, it was still talking for another 30 seconds.

“Unexpected item in bagging area” is one of those things that makes you long for the days of real customer service.

But even when it’s a person, they don’t count change out correctly, and many lines have those automatic change dispensors. Sometimes it’s too much for them to say “Good morning.”

And PLEASE, stop putting the dollar bills in my hand, then coins on top. That’s a recipe for lost coins. (Wouldn’t be a problem if change were counted correctly.)

Dave Simon 15 Aug 05

Another bad thing about the self-checkouts is the normal visual clues we have to show us which side to stand on are all removed.

No cashier. No rack of magazines and last minute items. Etc.

I’ve seen too many people start on the wrong side of a line and then turn around to the correct one. Perhaps they shouldn’t alternate sides?

John Y. 15 Aug 05

In some stores, I’ve gotten around the “unexpected item in bagging area” error by putting my foot onto the bagging scale and leaning on it; sometimes it won’t let you do anything, but in some stores it lets you proceed normally even though the scale is maxxed out. It’s a real time-saver, although I suspect the store management wouldn’t appreciate it if they saw me.

JF 15 Aug 05

Ahh, the old foot on the scale trick. That’s some great Contingency Design.

Tony 15 Aug 05

I don’t use the self-checkout because I know all the above-mentioned problems will mean that I will inevitably get stuck in line behind someone who is struggling with all of the above. Also, I have 2-year-old twin daughters, and it’s just easier for me to let someone else ring me up, while I try to keep my girls from getting into stuff. :)

ozmm 15 Aug 05

Self-checkout at my local Kroger is great. Big, easily readible buttons on a touch screen. I’ll never stand in the human line again.

Cameron Barrett 15 Aug 05

A good comparison study would be that of the credit-card interfaces at the gas pump, which are not quite perfect but certainly years ahead of the self-checkout contingency design. I used to avoid paying at the pump with a cardit card because I would almost always screw it up, but now I find that it’s pretty easy, no matter what part of the country I’m in. My only complaint is how they make it nearly impossible to grab the receipt, which is stuck behind this plastic flip-up thing that people with large hands have a really hard time fitting their fingers into. I once spent almost 5 minutes trying to extract a receipt from a pump once, pissing off the cars behind me waiting for gas.

Brad Sorensen 15 Aug 05

A good question mentioned (by Caleb) is what are self checkout machines trying to solve. With the answer to this you can better critique the system. Is it better customer experience? Is it to save the cost of employee’s? Is it to reduce the line-ups at the other check-out? Is it to meet the targeted IT Infrastructure spending allotment? What problem is the company who developed the software trying to solve vs. the corporation who bought the technology vs. the store who implemented the technology? Maybe the machines are doing exactly what they were intended? Maybe they reduce the line-ups by 5% which is what the tech company promised and what the store manager wanted? Maybe the user experience they are measuring is the act of choosing to self check-out vs. having an employee check you out. Granted, your experience using the system, for good or bad, is valid on its own; however I don�t always get the impression that a persons experience is a primary concern. If it was, maybe the 5% could grow to 45%, who knows.

Michael Armstrong 15 Aug 05

Personally, I like the self-checkout lines. Although from a UI perspective, they leave a lot to be desired. That they’re measurably better than getting a regular cashier is just sad. Very sad.

In my mind, they don’t go fast enough. I’m with Dave Simon in that the incessant chattering of the machine gets tiring. I spend too much time waiting for the machine and long for an “expert-mode” where I can just scan stuff, bag it and go.

Also, by using the machine aren’t I actually saving the store money? That’s time their (surly) cashiers can spend being rude to other customers. If enough people use the self-checkout, they don’t have to staff as many people. Why aren’t I getting a 1% or 2% discount for doing part of their job for them?

Adam C 16 Aug 05

Alot of people have brought up an interesting point. It’s not the concept but the design that matters. Like John Y. points out. Would 37signals like to provide the ideal self checkout?

Stephen 16 Aug 05

I think a good rule of thumb is ‘design for your mom.’

My Mum can email, use a mobile phone, record using the VCR, browse the web, use mailing lists, etc. However, all were a painful journey for her, and at times, me. When she sets out on a train journey she will plan everything ahead, noting down routes, times and fares. She would like her computer interfaces like this… a manual is to give authority rather than guidance.

I�ve always thought those who claim they are not savvy computer users are actually just unconfident computer users.

My mum can nearly always guess how to use to device, but is simply afriad of trying. I’ve tried for years to alleviate the fear of anything other than “do you want to discard this?” or “delete?” but she is still quite convinced that clicking the wrong link will lose her work. If only persistent state computing with universal undo were here already.

Trial and error is a huge part of becoming an advanced user of any system. Reducing apprehension enhances confidence.

When staying at my parent’s, my book/film/program/conversation is frequently and urgently interrupted so that I can be asked “I click okay, right?” My reply is usually an impatient, “well take a risk, try it.” The idea that the computer is not to be feared is not helped by their use of spyware, bloatware, “My” Documents, and virus infected Microsoft software.

For my mum the biggest problem is that the “are you sure?” prompts almost never give you the option of “no.”

Jeff 16 Aug 05

I hate the fact that when I go to Home Depot now there is usually only ONE register open - they are almost forcing you to go to the self-checkout. Wait a half hour to be rung up, or deal with our crappy system and do it yourself.

Personally, I feel as though part of the price you pay for anything is going to payroll - and if I’m ringing myself up, I should be getting some sort of discount, because the company isn’t paying for someone to stand there and ring me up. When I start getting a 5% discount on my purchases, I’ll happily use the self checkout lines.

Paul 17 Aug 05

When I start getting a 5% discount on my purchases, I�ll happily use the self checkout lines

This stood out to me as scary: I thought almost everyone, at some point, worked in retail. It would be a shame to see a reduction in Home Depot�s payroll, I�m happy that 5% of the purchase price goes to a person who working a thankless job; I�d rather than then a 5% discount to a clumsy touch screen and barcode scanner combo.

Furthermore, when these critical user interfaces are bad, its catastrophic, and when they�re good, its merely adequate. Cashiers/salespeople will always represent the highest-end of customer service, just like real wood/leather will always be classy and synthetic materials will never be a status symbol.

Aside from being high-end, there are practical reasons for having a real person behind the register: The population is aging, and older people like to talk to someone when they�re out doing their shopping. They also tend to have arthritis, or impaired vision, which makes using the touch-screens very tedious. Coupled with the lack of human interaction, Home Depot et al are almost asking for reduced business from this demographic.

Wesley Walser 17 Aug 05

Can I just say that I thought the illustration for this article was simply halarious, probably because I was one of those people today. You just feel like a moron when your lively hood is determined by your work with computers, but you still have to have a 18 y/o drop out come help you check out.

Yes, I had to get help…

Jason Anderson 17 Aug 05

I’d be interested in some conversations with the community about how to make these things better. I’m part of a company which writes software for kiosks (although we haven’t done any of the self-checkout apps) and it’s pretty easy to see that the whole industry could improve when it comes to interactions with customers.

It’s a new enough medium (relatively speaking) that not all of the interface issues haven’t been worked out yet, but we are thinking about it. Personally, I’d love to see kiosks designed with the same focus on simple, human design that’s taking hold on the web.

Granted, there are some poor experiences out there. We want to make them better. How can we get some conversations going?

Jeff 17 Aug 05

This stood out to me as scary: I thought almost everyone, at some point, worked in retail. It would be a shame to see a reduction in Home Depot�s payroll, I�m happy that 5% of the purchase price goes to a person who working a thankless job; I�d rather than then a 5% discount to a clumsy touch screen and barcode scanner combo.


Oh, I’ve certainly worked my share of retail. The point being however that at stores like Home Depot, they are already reducing payroll by cutting the cashier positions in favor of the self checkout.

In places where they haven’t yet cut down the staff (like supermarkets) they want you to see the self checkout as an advantage. Save time - do it yourself. Bunk I say. They need to make it attractive enough for me to want to deal with scanning and bagging all my own groceries - using a system that will likely fail at least once during the process because I didn’t properly put an item right where it was supposed to go. Then, when the sytem locks up, I have to wait 5 minutes for the front end manager to see that my light is blinking and come fix the problem. Where’s my advantage?? I’m paying the same amount for my food as the people who have TWO people waiting on them - the cashier and the bagger.

Jason Anderson 18 Aug 05

To be fair, do the self-checkout lanes really fail that often? I may have just been lucky, but I’ve had very few major problems at one. I’ve occasionally seen the weight issue (annoying) and one time the machine didn’t have enough change, but most of the time it actually is faster for me.

Of course, if stores eventually close all the normal checkout lanes and move everybody over to self-checkout, aren’t we back to the same problem with lines?

Rob Cameron 18 Aug 05

I love the self-checkout when I’m the one using it. If there is more than one person in front of me then it’s my worst enemy and I’ll go right to the regular checkouts. Seems like the average person just takes too long to use the system. There will just always be people that want to stop and read every screen and every option, while I’m used to it and can go right to what I need.

While I’m normally out the door in 30 seconds, I have almost never seen another person have a smooth checkout experience. The “incorrect item in bagging area” gets them every time. I’ve noticed this happens with really light items. They really need to remove that requirement — if someone wants to steal something, they’re going to do it. Trying to calculate the weight on every single item is just destroying everyone else.

Joe Schaller 18 Aug 05

Great comments all! I’ve been in the cash register / POS business for 25+ years and have seen a lot of innovation. The comments on the over-use of “voice” are a throwback to when RC-Allen (?) came up with the same technology for POS around 1987 or so - it lasted for about 6 months until everyone got so annoyed with the sound it had to be turned off.

Kiosk technology does not use less labor (it is never been saved, just redeployed - that cashier just became a stock person, etc.) At least that has been my experience with this technology in the restaurant business. It really helps to smooth out queue’s - people tend to arrive in bunches, not a smooth flow, so the self-checkouts allow more avenues of service when a crunch comes - but one cashier can equal the capacity of four self-checkouts. Having a cashier stand around for an hour for the 10 minute rush is a waste of time and ends up making the cashier tired / lazy / surly as a result of sometimes long periods of inaction.

Abdul Ovaice 19 Aug 05

The saddest thing about these systems is most usability people can’t figure it out. I almost stole somethingt Home Depot. And most of the time a store clerck has to come by and help the customer.

Peter Jacobson 21 Aug 05

I’d say that airline kiosks are pretty good though. Very simple interface, large buttons and text, easy “outs” if you’re confused, and you call up your account/itinerary easily (thereby leveraging the total loss of privacy incurred by having ALL your credit info available to multinationals in real time).

Never tried a self-checkout anywhere else though!

gareth jones 15 Sep 05

kind of reminds me of my mouse hovering around the basecamphq homepage trying to find the log in button…