Sergius Kagen (1909-1964) was a member of the faculty of the Juilliard School of Music and had this to say regarding the studying of singing:

In my experience, I have become aware of the fact that too many young people who hope to become professional singers believe too much in and expect too much from the processes of study. . . . [Study] cannot be expected to endow the student with faculties he may not possess by nature.

SOURCE: Sergius Kagen, On Studying Singing (NY: Dover Publications, 1960), p. 4.