I'm the first to admit that I'm one of the three or four weakest players at our weekly (for funzies only, of course) poker game. I figure I'm doing pretty well if I can keep the (theoretical) losses down to single digits, eat a few Cheetos, drink a little bourbon, and not go face down in my few remaining chips while I wait for Presto Shang (aka Pokey) to bet. There's genuine camaraderie, of course, in addition to booze and snacks—actual laughs among like-mindeds, and the occasional interesting flare-up of difference, too.
That's why I play (plus, it's about the only regular social outing I get now that I'm a dad); but why do I play so poorly? I think the real answer is that I just don't care enough about the game itself—which is ultimately pretty boring most of the time—to take the time to study things like betting strategy, pot odds (not to mention implied pot odds), and all the other nuances that make the difference between the poor-to-average player and the competitive player. Anyone that's ever tried to read one of those "How to Win at Hold 'Em" books knows what I'm talking about. My eyes start to glaze over just thinking about it.