Also, there can be a difference between 'working hard' on a song and preparing it for performance. 'Working on it' may involve vocal technique, memorization, interpretation, while preparation for a 'stage' may involve dealing with psychological and emotional demons, consideration of how best to convey the song to the anticipated audience, a more thorough training of 'muscular memory' to preclude the kind of minor gaffs that may be inconsequential in informal circumstances. By way of comparison, I've known many accomplished fiddlers who clearly worked very hard on their music, - but who never developed a 'professional' type of presentation.