Because when people started lose money there, they wanna bet more to get the loss back, but most of them failed and keep losing, like me, damn i was good at gambling, but after big losses on trading altcoin, i had bad luck on gambling now. I can't win now, what a tragedy.
This is what when a loosing phase is running that time it is better to play low because you cannot defeat the lossing phase. for some days play low volume or better take rest and come back with full confidence. This way you can win back as everyday you cannot be in profit.