[pzhon]

When there are more limpers, trash hands become worse, and it is more clear to fold them for 1/2 of a small bet.

Against one limper, there is a decent chance your hand is good if you even flop a pair. Against many limpers, you can't profitably continue with just a low pair.

If you were getting really good pot odds against one player, you could play any two cards. If you get really good pot odds because you have to come up with the best hand out of 10, you still need to fold Q2o.