Far to many of the responses here are devoid of situational play. "Calling" or "Limping" is a legitimate play in a poker game, made at the right time, to maximize your expected value.
To say that limping is lost chips, over simplifies the action.
Furthermore, the question does not ask us whether we are limping pre-flop, or on another round. Read any good poker book and there are all kinds of discussions on when to limp and when not to limp - far too many to discuss here.