The vast majority of human beings follow Dharmas that entail the performance of Karman of some kind or the other.  Relatively, a very small percentage follow Dharmas that entail the pursuit of knowledge. In their case too, they have to follow a modicum of karman necessary to stay alive and follow their Dharma properly.  Both Karma as well Jñyāna Yogaḥ have the same end goal, namely Mokśa.

What is the nature of Karman that constitute Karma Yogaḥ? At the immediate level, they are actions needed to sustain life and make the wheels of life go round and round.  But that is not the end goal of Karman performed by mankind as a whole. At the highest level, the aim of all Karman is final liberation from repeated bondage in Prakṛti or Matter. Karman interestingly enough, perpetuates bondage in birth after birth if done improperly. Done properly, Karman can help secure Mokśa or final liberation.   Ordinarily, in a given birth, every human being tends to add more Karman to his or her account reckoned from the beginning than to reduce it. Mokśa cannot be granted to one whose account contains a residual balance of karman awaiting fructification for the obvious reason that human beings cannot escape the consequences of Karman. If there is residual balance of karman at the time of death, whether the consequences be good or bad, the Self has to take on a new body to experience the fruits and to thereby discharge the Karman. 

If one views any residual Karman as a debt to be paid, it is reasonable to assume that one cannot get release until all pending debts have been repaid.  One has, therefore, to use every embodiment one has been given to reduce the past debts to the maximum extent without creating fresh debts.  One has to repay all of one’s debts before becoming eligible for Mokśa. The slate has to be clean.  If not, rebirth and repeated embodiments are inevitable.  Aṣṭāṅga Yogaḥ is one field which provides good scope for the performance of Karman correctly to wash away the cumulative sins of the Yogi and to secure Mokśa over the short time-span of a few births in the worst case.

Jñyāna Yogaḥ is the pursuit of such knowledge as will secure emancipation when the time comes.  But it also needs certain minimum quantum or elements of karman for the sustenance of the body.  No Yogi engaged in Jñyāna Yogaḥ can remain totally actionless. Of the two apex yoga disciplines available for securing Mokśa we have mentioned above, Karma Yogaḥ is, all said and done, better than Jñyāna Yogaḥ for certain reasons.  Firstly, for the overwhelming proportion of Mankind, Karma Yogaḥ is a natural discipline that can be pursued without second thoughts.  Though defective, it is free from the liability of interruption, failure, and fall.  A person engaged in the Karman of a given Dharma all his or her life just as his ancestors did in the past, is inherently qualified for it.  Because of this inherent qualification for Karman, while pursuing Karma Yogaḥ, if untimely death were to occur in any one life before gaining success, it would not matter because in the very next birth, that person would be able to resume his or her Karma Yogaḥ at the point it was interrupted and to make speedy progress thereafter towards success using the experience already gained up to the time death occurred.

Jñyāna Yogaḥ is difficult to pursue.  It is fraught with the risk of errors and failures.  In principle, it is fundamentally unnatural for anyone conjoined with Prakṛti.  It becomes inevitable for all human beings when they find themselves in embodiment soon after birth.  Failure and fall at any stage during Jñyāna Yogaḥ would compel the Yogi to start again from the very beginning.  All the progress made before a fall from Yogaḥ may have occurred would be lost.