Here is, I think, a fairly non-controversial statement.

Testers notice stuff.

It’s kinda our job. And I suspect that people who are drawn into the field have always noticed things, only now we get paid for it.

Here is a quick anecdote from last weeekend to illustrate this. The boy was going to a birthday party at one of his good friend’s house, but we lost the invitation. Which of course had the address. Through a bit of logic and memory comparisons we figured out which house we thought it was. After dropping the girl off at work the morning of the party I drove by the house and saw his mom’s and grandparent’s cars in the driveway (we live in the suburbs; we don’t park cars in the garage) confirming the address.

When I mentioned seeing the cars in the drive to my wife she drew a blank. She had no idea what car they drove though one of them was always at the school at pick-up time. She is a veterinary technician and notices things, but her field of view is very narrow; this specific animal and its health.

Testers though, notice a whole lot more. Our brains are taking in all the stimulus they can to try and make sense our current context and how things fit into it. Most testers who have been doing the job for awhile have experienced the something is wrong on the screen, but I just can’t quite figure it out feeling. We have subconsciously noticed a bug, but it just takes a bit to bubble it to the surface.