The left vote against conidence motion. If the gov fail, general election come. As per the present political situation no body get obsolute majority. BJP allies get near 220 to 230 UPA may get 200 to 220 and if to rule left support may require for BJP or UPA. Then what left will do. They have to answer for this question before they cast against the confidence motion.
Otherwise call them "The Useless Irresponsible Front"