At the age of thirteen, after having purchased his first guitar and begun taking his first lessons from fellow New York native Joe Satriani, Vai became obsessed with the discipline of practice. Vai's practice routine, consisting of a rigid and structured regimen of ten-to-fifteen hour-a-day practice schedules, became the basis of his work ethic for the rest of his career. During his employment by Frank Zappa, Vai transcribed and played very rhythmically complex music, believing that if started slow and perfected, any piece of music could be played.