According to Wikipedia, participation bias means that: “the result of a study can become non-representative because the participants disproportionately possess certain traits”.
People are picky, we like to work with people that we understand. But understanding usually means that we have something in common, opinions for example. That makes research pretty tricky: we tend to focus on information that we like to hear.
Let’s face it, a lot of companies still find it difficult to test their products with real users. We all know that testing is important, but it’s a lot easier to ask your colleagues for assistance then to approach real customers, isn’t it? Yes it is, but it can turn out to be very expensive. Even if the test results are bad, the general opinion can be much too positive. Why?
- Because nobody wants to throw away company work. It seems like a waste, so even small projects can be too big to fail.
- Because everybody likes a challenge. “We know it’s not perfect but we can make it better if we {insert a lot of work here}”.
- Because we have our own priorities: “Maybe this could save me a lot of work, even if the customer has a bad experience”.
- And finally, just because we want to be friendly to each other.
It’s nice to work with colleagues. But it’s a lot better to work with customers.