Sec.12 (1) of Hindu marriage act 1955

Meaning of voidable marriage: A voidable marriage (also called an avoidable marriage) is a marriage that can be cancelled at the option of one of the parties through annulment. The marriage is valid but is subject to cancellation if contested in court by one of the parties to the marriage.

Sec.12 (1) : Impotency is a ground of voidable marriage under Sec.12 (1) of the Hindu marriage act 1955

Failure to consummate a marriage is a ground for divorce or an annulment

One of the essential conditions for Hindu marriage is that neither party should suffer from a mental disorder of such kind or to such an extent as to be unfit for marriage, and the procreation of children of either party is important, then such marriage is voidable at the option of another party.

A voidable marriage has to be declared Null and Void by a decree of the Court on the application of the aggrieved party.