It's probably escape mechanism on your end or you want to find any excuses for your loses. And I might say that majority of us here could go on that kind of mentality, winning in the beginning and then losing in the end.

I even watch some players really losing their cool on a slot machine in a land base casinos, kicking the machine itself and the security have to restrain him. So maybe he can't control himself that time and winning early but all of a sudden when he think that he is going to win big, suddenly the momentum shift against his favor.