Members of the Congress Party have different compulsions and different ideologies. A Congress members stays in the party not because of any loyalty but because of a calculus of costs and benefits. So long benefits outweigh the costs, a member will stay in the Congress and rationalize it for the public. Membership in the party provides access to other influential members. However, there are costs as well.
Party is in decline.
There are so many splintered groups in various parts of the country that has reduced the advantages of a national Party. The widespread corruption among its leaders have tarnished its image. The Party record in winning elections is poor and further diminishing. It helps no one if such big names as Kamalnath and Buta Sing lose from safe constituencies. The down side of running the government from the back seat is that the Congress party member has to bear high costs of being associated with an unpopular and non functioning government.