Why they need an excuse to hold your account. Legit casino like Stake will allow withdrawal instantly without the need to hold someone account assuming that you win it fairly.

However scammer casino has a lot of excuse they can throw at you such as delaying KYC approval, multiple account, abuse on bonuses and worst is the general violation of the ToS without any specific details which they are allowed to do due to their ToS that you agree which they can hold/freeze an account whenever they want without explaining further.

In conclusion, there’s a lot of possible excuse so just play on reputable casino to avoid this headache.