The path of Ashtanga Yoga or Jnana Yoga is called Pravritti marga. Here aspects of the mind, intelligence and inner nature are studied in the light of material nature and worked upon. Even on the paths of Jnana and Ashtanga unless one takes support of the superior path of Bhakti, perfection is impossible to attain. In these other paths the living entity loses his personal identity in the Absolute and thus he is not qualified to serve.
Bhakti is the path of Nivritti marga or the non-material path. Here one simply surrenders to the higher agent of Sri Guru who is the agent of the parartha or the highest principle of Bhagawan who is non-matter. Since the source of our inner nature as understood by the Shastras is non-matter, one simply surrenders to that aspect without struggle and gets out of material nature. Other margas require rigorous practices and gymnastics of controlling and throttling the mind which calls for adjustment of Varna/Ashrama , time, place and circumstances under which specific practices are undertaken with strict rules. However in the Nivritti marga of Bhakti one may belong to any Varna or Ashrama whether householder or a renunciant without botherations of time , place and circumstances and practice it with consummate ease.. When one surrenders to the Sadhguru completely one’s free-will in unrestrictedly, one is taken over by the paratattva or the Guru principle which cleans the individual of all material propensities. By this cleansing one’s mind and hence consciousness becomes fixed in the Supreme Person according to the descriptions available in the Bhakti Shastras. Therefore bhakti gives detachment from all things which are materially motivated. The topmost devotees of the Lord , the gopis, were householders. The never knew Sri Nandanandana as the Supreme Person , yet their attachment to Him gave them the status of being the most elevated devotees of the Lord.
For people who are not in Bhakti, Bhakti is too difficult to grasp with mundane intelligence. This even confused Brahma and Uddhava as to how the Gopis attained such an elevated position. They never rendered any specific devotional service as they continued to do their family chores apart from loving Krishna. The point to be noted here that whatever the Gopis did , they were fully devoted to Krishna in their mind throughout the day and through the year. Their only qualification was their consciousness was pegged on Krishna, fully devoted to Him like no other being in the three worlds. This is the exact meaning of nivritti. It means working only and only for Guru and Krishna.
One is looking for happiness in other paths where you are taught to focus on that which cannot be imagined. Even if one for argument sake succeeds, one loses his identity in oneness. If the identity itself is in question, there is no question of experiencing happiness. Nivritti marga is the path of service and the path of service can be the only path to happiness.