How many testers is enough when it comes time to comb your site prior to launch? Four? Six? Eleven? As many as you can get?
This depends upon whether you have already conducted usability testing. With the economy what it is, it’s probable you didn’t. And while that’s unfortunate, it’s also reality. So, you will want to fold some usability testing into your QA. Because even pseudo-usability testing is better than none.
With that in mind, it’s always better to err on the side of more testers… especially if they are volunteering their time and budget is not an issue.
Five testers is okay, though I prefer six as a minimum, seven is better, and eight better still Why? Well, not so much to catch mistakes (though there is that — no one catches everything, so the more testers there are, the better the chance of everything getting caught.) But it’s also that you need to make sure you are covering all the major platforms and browsers and versions, and five just might not be enough.
You also want more testers because inevitably there are testers who are just lame. Lovely people, but lame testers. I remember when we were testing Julia Quinn‘s site and Eloisa James, the queen goddess of the English language, submitted four solid pages of fixes (including catching an i-before-e issue on a header graphic that I am embarrassed to say none of us saw in production.)
Another tester said, merely: “Looks great! Love the color!” Again, lovely person, brilliant author, lame tester.
With only five testers, you don’t really have room for anyone to be lame. Or if you do, then the other four better inspect like drill sergeants. You see my point?
So keep hunting. If you can find another couple of testers, it really is in your best interest. Believe me, I understand the issues of trying to conscript people for this. But a big reason we like to have many testers is usability-related. Invariably there are one or two issues with the site that made perfect sense to us, but which confound over half your testers. Recognizing and calling out jarring elements is a primary job of your testers. Maybe you can dismiss the comment when when only one or two people are saying “What the H?”, but when it’s four or five people getting tripped up, then we know we need to change that element. If you only have five testers you are hoping that everyone does their job and calls out the awkward element that tripped them up. But no one bats 1000. Ever.
So choose many, and choose well. You want people who would tell you that you have spinach in your teeth or toilet paper stuck to your shoe. This is no place for “Well, I didn’t want to insult you.” Instill in your testers the value of their letting you know everything, especially if the element looks confusing. Don’t let them assume it’s their problem. If you don’t get it, call it out.
Oh, and your significant other can’t test. Neither can your mom. They are too close. More on this and other testing issues in a later post.