Gambling is both combination of luck and your skills, but decisively we win by chance. Your bets are placed based on your already gotten knowledge as you have already said, of which you stake on those predictions within your risk tolerance level and accept any outcome of your bets.

My take on this OP,  is gambling isn't fun as well as either you lose or win. We all just take part in a probability game that is uncertain, we accepting this fact shades us from Ill feelings of which we keep betting nothing more or less.
Of course judging from normal Human perspective it won't be fun if don't all lie to ourselves, we all know and accept lose as part of game so it becomes fun when we lose then if am to put it this way. In essence gamble responsibly with your set rules so as not to reach a stage you become  emotionally unhealthy and then the fun dies off the game.