Yes. Stress, disappointment, and regret.

Kidding aside, if it's a material thing, I didn't achieve anything it yet because most of the time... or all the time, I'm losing my capital in gambling. I don't have any regret because at the end, it's my decision to gamble. For those who achieved anything in gambling whether they bought something because of their winnings, or they paid their debt because they won in gambling, you're lucky that you've achieved those things. Just always take note that learn to stop when needed.

I guess what I achieved in gambling is happiness. I mean I'm happy whenever I put a bet on a team while watching the game (sports betting). Happiness surely is costly, eh?