90% of the people going to loose that money hence it is most of the time benefit to the house. User will loose his/her money + signup bonus
I'd say 90% is too low, I think it should be around or even more than 95%. When the chance of people can complete the rollover requirement is 10%, I'm sure there will be no more sites offering such kind of bonuses because it is not good for the sites.
My estimation is also over 95%, AFAIK, I never heard anyone who completed and profited from 1btc bonus plus 1 btc deposit, very easy to bust 2btc before completing high rollover, a few lucky guys can get 1.X btc in the end, super lucky guys may get many coins profits, but only few.
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