By Bono.
I'm enjoying Bono's Autobiography. It's got me relistening to U2's old music. At one point Bono states that U2 originally wrote their owns songs because they weren't good enough to play others. Their song writing style was meant to showcase what they could do and avoid what they couldn't. Two cord guitar riffs instead of three. Over their first four albums, you literally hear the band become better musicians.
