G.B. Lamperti (italian singing teacher):

“Your art is the fulfillment of your elemental desire to sing. Your growth is stimulated by what you hear and understand.
If you faithfully do your daily practice, without anxiety about the result, you will find yourself competent in the end. You must stop at no stage of progress, anchor to no habit, be satisfied with no result, exult in no success.
All the details of singing are finally marshaled under one commander, emotion, the original source of song.”