I played a hand recently that really highlighted some of the extremely common low-limit mistakes we see all the time.
I limped in on the button with 8Ts behind 3 limpers in a loose medium-stacked game (I've had a good run and have everyone at the table more than covered.) I flopped a gut shot straight draw and a backdoor flush draw. And early position player bets out about a little over 1/4 of the pot, two players call after him, so I call. The turn brings a fourth card to my flush, and the early position player again bets out a little over 1/4 of the pot, so I call again. The river completes my gutshot, he bets out and I raise 3x. He tanks a bit before calling, and throws a fit when I turn over my straight, berating me for calling him down to the river with a gutshot straight draw. LOL.
I commented that I just had a feeling it was going to come in, and that everyone has to get lucky sometimes. He snarled and said, "yeah, it's better to be lucky than good, isn't it." It always amuses me that people will give you the correct odds to call them down and then think that you have misplayed your hand by doing so. It is also interesting how when you have multiple draws and one of them hits, people always focus on how unlikely the draw that hit was, and ignore the fact that you were actually drawing to 12 outs, not 4 (in this example).
What kind of other extremely common mistakes to you see all the time by low-limit players who consider themselves good and berate others at the table?