Once you complete the wagering requirements, you can withdraw your funds from the online casino through the cashier. Casinos don’t like when players withdraw their money, though, because it’s better for them if the money is used to wager. That’s why they came up with the option of „reverse withdrawal”.
Online casinos take time to process withdrawals, usually 24-48 hours. They say it’s because there’s a queue, but in reality they want players to be tempted to cancel the withdrawal. When you request a withdrawal, you cannot use the money in any way until the window of time passes. Any time before that you can use reverse withdrawal to get the funds transferred back to your casino account, ready to be wagered. The temptation to do that is especially big when your last winnings were big, or when your casino account is empty but there is money waiting to be withdrawn.
It’s important to avoid this temptation by following the budget you prepared for yourself. There are practical ways to not give in, such as keeping enough money to play with and withdrawing the rest. Not using the casino at all during the window period is another good idea.
Some online casinos are aware that reverse withdrawal doesn’t help with responsible gambling. They shorten the window to 12 hours, let players bypass it or remove it altogether.