And this is why:
If you laugh, which is to draw attention to the ref mistake, the ref will later on be more likely to call you strictly so that he can avoid being put on the spotlight for a mistake call, the ref will essentially start calling fouls against you with a safety factor, because now he is thinking there is less room for error
If you play it cool, then he won't stress messing up on a call with you, the ref will be generally more at ease when deciding if he will call something on you or when someone fouls you
At least this is how it works in rec league, but I work on the assumption that NBA refs and players are humans too and they should basically react the same way,
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