Most of the time, things we wish for come at the most unexpected times. Has it ever happened to you? Why would it be different in gambling? I just feel like greed leads to more losses, like some kind of karma for desperately trying to hit the big one..
You could actually try and see if some gambling casinos record the winners in their gambling games. I found one with Cloudbet here and their pretty interesting games as well as situations.
Hitting big wins through gambling goes wrong most of the time because while I'd take at least two thirds of that money and invest it in something, most others will gamble it all in a matter of days, weeks or just months. Different perspectives lead to different outcomes.
For example: I think my largest win was somewhere around 0.2BTC. When I won it, I took 0.19BTC and invested it all while gambling the remaining 0.01BTC. Guess what happened to the latter within hours... poof!