When the world caters to single hits, you don't need to aim for a career as an artist. You can sing one song, write one book, make one movie and leave it at that if that's all you have in you. There may be fans who clamour for more, but for the most part the world will move on and leave you alone. That's one advantage of society's shrinking attention span.
Mokalus of Borg
PS - And if it turns out you do have a second work in you, that's okay too.
PPS - You can keep going as long as you like, and stop before your quality drops.