To clarify things better here is an example : if you were to deposit $1000 and win $200 in your first few games then you wouldnt be able to withdraw your winnings or even your deposits without wagering at least $5000. This means that 80% of the time, you would lose your money before reaching the required amount.
In my opinion this term is unfair. I am not attacking any specific casino, but I do believe that if users were aware of these requirements they would be less likely to deposit their money in such casinos since there are other casinos without such stringent requirements.
My first time of getting to know about a thing as this, this is completely unfair and I could possibly tell that a casino with such a term is being managed by criminals.
@OP, This thread would have been more informative if you mentioned the name of the casino in question, so that some of us do not end up making the same mistake you made on this same casino, on the few casinos I've played on, including Stake.com, never encountered such a rule, so for me, there is absolutely no reason whatsoever, a casino should impose such a high wager requirements for withdrawals on its customers, its an act of robbery, and such casino should be boycotted.