[tewall]

If there are n opponents, and the pot the first time around is P then you are getting P:1 for the first call and P+n:1 for the second. Even though your chances are worse (in view of the raise), they won't be enough worse to make the improved P+n:1 call not worth making.

The problem of getting strung along for extra bets is why limping in early is risky and why the hands you can limp in differ depending on how loose and passive the game is.

The later the position you have, the less likely someone will raise behind you, and worth your position in later rounds drawing hands will be easier to play.

The way to avoid the problem is to be very cautious when limping early, being careful to do so in games where you're likely to get many players seeing the flop and they play passively.