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.72 "What do I put here?" asks the user.Possibly because they don't know the answer, butpossibly because they know the answer for their computer, only they're not using theircomputer, they're using yours, which they've never seen before, in a usability lab, wherethey've never been before.So you have no way of knowing whether your UI is good enoughfor this question).At Juno, we knew that the dialog in Figure 13-1 was likely to be the sourceof a lot of confusion.People certainly had a lot of trouble with it in the lab, but we weren'tquite sure if that was because they didn't understand the dialog or if they just didn't knowhow the lab computer was set up.We even tried telling them "pretend you're at home," butthat just confused them more.Figure 13-1: The dialog that we couldn't figure out how to usability test.Five minutes later, the program asks for the user's address, and then it crashes when theyput in their zip code because of a bug in the early version of the code that you're testing.Youtell the next person who comes in, "when it asks for your zip code, don't type anything in.""OK, sure boss!" But they forget and type the zip code anyway, because they're so used tofilling out address forms onscreen from all the crap they've bought on the Web.The next time you do the usability test, you're determined to prevent these problems.So yougive the user a nice, step-by-step, detailed list of instructions, which you have carefullytested so they will work with the latest development build of the software.Aha! Now,suddenly you're not doing a usability test.You're doing something else.Charades.Theatre of the Macabre.I don't know what it is, but it's not a usability test because you're justtelling people exactly what to do and then watching them do it.One solution to this problem has been to ask people to bring in their own work to do.Withsome products (maybe word processors), that's possible, although it's hard to imagine howyou could get someone to test your exciting new mailing list feature if they don't need amailing list.But with many products there are too many reasons why you can't get a realisticusability test going "in the lab."Usability Tests Are Often Done to Resolve an ArgumentMore than half of the usability tests I've been involved in over my career have been theresult of an argument between two people about the "best" way to do something.Even if theoriginal intent of the usability test was innocent enough, whenever two designers (or adesigner and programmer, or a programmer and a pointy-haired manager) get into a fight73 about whether the OK button should be on the left or the right of the Cancel button, thisdispute is inevitably resolved by saying, "we'll usability test it!"Sometimes this works.Sometimes it doesn't.It's pretty easy to rig a usability test to show therighteousness of one side or the other.When I was working on the Microsoft Excel team,and I needed to convince the Visual Basic team that object-oriented programming was "justas easy" as procedural programming, I basically set up a usability test in which someparticipants were asked to write cell.move and other participants were asked to writemove(cell).Since the audience for the usability test was programmers anyway, thesuccess rates of the non-object-oriented group and the object-oriented group weresurprise, surprise indistinguishable.It's great what you can prove when you get to write thetest yourself.In any case, even if a usability test resolves a dispute, it doesn't do it in any kind of astatistically valid way.Unless you test thousands of people from all walks of life under allkinds of conditions, something that not even Microsoft can afford to do, you are not actuallygetting statistically meaningful results.Remember, the real strength of usability tests is infinding truffles finding the broken bits so you can fix them.Actually looking at the results asif they were statistics is just not justified.Some Usability Test Results I Might Believe:Almost nobody ever tried right-clicking, so virtually nobody found the new spell-checking feature.100% of the users were able to install a printer the new way; only 25% could install theprinter the old way.There were no problems creating a birthday card
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