You can turn 5 failures into a success.

If you try and fail at something or multiple things 5 times the next endeavor you take will end in what you would consider a success. You must believe that you're capable of doing the things you failed at. If you have no background in medicine and try to cure cancer 5 times and fail, these failures will not result in a subsequent success. Attempting to convince yourself you have a chance when you know yo don't, won't result in a success either.

Edit. I want to clarify, you have to fail 5 times at what this power ends up letting you succeed in, not just any failure. Also in the case of gambling, you have to believe and/or try to win for those failures to count toward a success, no giving up or losing hope. Remember you miss 100% of the shots you don't take.

Edit 2. I realized i should have made it 6 failures and this was a missed opportunity to make a Lucky Number 7 power.