But not all problems at a casino will be found unless the gambler has gambled at that casino, so gamblers will review the casino they choose to gamble at and they generally don't know the problems at all casinos unless they check in detail at each casino to ensure the casino system is fair and does not complicate the withdrawal process.
A wise person is the one who learn from other people's experiences and mistakes. So, if many users say that they had a bad experience with a certain casino or that it is a scam (they need to be trusted users or if they present undeniable proofs) then you don't have to test the casino yourself and repeat their mistake.
If you don't have any other option but to try it yourself, then at least do it with a small amount of money.