I question my ability all the time.
I also question the ability of others.
I've gone through cold spells where nothing seems to work for me. During these cold spells I see not-so-good
players have winning streaks and think that maybe, just maybe, they are doing things that I should be doing. Maybe they're playing better?
But if I'm doing well and I see bad plays being rewarded, it's a whole lot easier to dismiss their wins as luck.
I remember playing a ring game and this guy kept pwning me. He seemed like he was playing crazy but he had my number every hand, calling every bluff, folding every time I had a hand.
He was cleaning up at the table.
When the game was over I logged off of the poker site
then looked him up. He was an incredibly bad player who was in the bottom 20% of players and had lost a lot of money. I guess he was just having a lucky run.