One of my favourites is “Street addresses contain street names”. I recently had an experience where the piece of software didn’t allow you to alter the country you lived in so e.g. I’ve lived in the UK for over 4 years but previous to that I lived in Ireland. Ireland doesn’t really use postcodes or street names once you get outside of the towns so the format of my previous address didn’t match the expected format of the software. I couldn’t adjust the country in the hopes it would then make these fields not required, a previous address was required so I just had to abandon the software.
The conversation got me thinking, are there falsehoods that testers believe? Maybe you previously believed a falsehood but now you don’t, would you be willing to share that?
I previously believed that security testing should be done by a security tester, performance testing should be done by a performance tester, etc. That’s fine in certain situations but not all. I soon learned that as a lone tester you pretty much have to cover those areas yourself and then contract some of the bigger stuff out if you can.