Why does David Guetta get credit for his songs when he doesn't sing?

I just don't get it.

Quote from xx-jenn-xx

he's a dj and a producer...he gets credit for producing...you don't need to sing if you're a producer...or a dj

Ok, so if I'd been asked to dance or sing (which I've probably been asked in the past), I'd chose sing. If not, then producer or DJ.

Quote from xx-jenn-xx

he's a dj and a producer...he gets credit for producing...you don't need to sing if you're a producer...or a dj

Do you like his songs by the way?