SB 11.15.33

antarāyān vadanty etā
 yuñjato yogam uttamam
mayā sampadyamānasya
 kāla-kṣapaṇa-hetavaḥ
Synonyms: 
antarāyān — impediments; vadanti — they say; etāḥ — these mystic perfections; yuñjataḥ — of one engaging in; yogam — connection with the Absolute; uttamam — the supreme stage; mayā — with Me; sampadyamānasya — of one who is becoming completely opulent; kāla — of time; kṣapaṇa — of the interruption, waste; hetavaḥ — causes.
Translation: 
Learned experts in devotional service state that the mystic perfections of yoga that I have mentioned are actually impediments and are a waste of time for one who is practicing the supreme yoga, by which one achieves all perfection in life directly from Me.
Purport: 

It is common sense that whatever is a useless waste of time should be given up; therefore one should not pray to God for mystic yoga perfections. For a pure devotee, who has no material desire, even impersonal liberation is a useless disturbance in his life, and what to speak of the material perfections of yoga, which cannot even be compared to impersonal liberation. Such mystic perfections may be wonderful for an immature and inexperienced person, but they are not impressive for a learned man who has understood the Supreme Personality of Godhead. Simply by obtaining Lord Kṛṣṇa one dwells within an infinite ocean of mystic opulences; therefore he should not waste precious time pursuing separate mystic perfections.