I think the biggest mistake is people treating prop firm accounts like cash accounts, and visa versa.
The most successful prop firm traders I know spend thousands per month on fees, but double or triple that investment. Take FSP, he’ll line up accounts one after another taking the same move, such as buying a pullback. Maybe the first one or two blows but the next few have caught the bottom of it, with size. Not copying trading them at all. Nobody would trade a cash account this way, but it’s effective with props.
prop firms are a game, you have to learn how to play the game with the capital you have to invest in them. Risk management between a prop account and cash accounts can and should be different IMHO. Milk them and dump into those profits into a personal account where you can work on a real trading system such as ORB, momentum, IB etc with ris management being priority (the only thing you can control in the market is your own risk)
Better yet, start using your personal accounts (or live prop accounts if you like to give firms 10% or more) to hedge your prop firm evals and SIM funded accounts!