The definition of confirmation bias is to believe what you want to believe. Basically, when someone tells you something or you craft an opinion, sometimes we stick to it too much and don't let our evaluation smoothly evolve. This is why confirmation bias is one of the biggest errors that evaluators can have. I'll give you an example:

Jayson Tatum scores 2 points on 1-10 shooting in his first game at duke. that's literally the only game you watch of him, and you're very low on him. he was blown by defenders and didn't show many playmaking flashes.

in the same game josh jackson wows you with athleticism, defensive "potential", and playmaking flashes. top 3 preseason prospect in your eyes.

this is the definition of confirmation bias, and why we have to watch the good, the bad, and the normal against different kind of competition. and sometimes we do that, but we don't allow the new intel gathered from all types of games to improve our evaluation. so just a quick thought about scouting any type of player in basketball.