Bhagavad Gita, Chapter 11, Verse 48

Neither by the study of the Veda and Yajna, nor by gifts, nor by rituals, nor by severe austerities, am I in such Form seen, in the world of men, by any other than you, O great hero of the Kurus.

No amount of real effort, study, ritual, or discipline, is named here as capable of earning this on its own.

Krishna lists several serious, legitimate spiritual practices and states none of them alone could have produced what Arjun just saw. What made it possible is named as something else entirely, grace, not achievement.