"I thought 'pop' was a term of abuse, it seemed sort of insulting and lightweight. I didn't realise how cool it was. Because some of the best music does have a lightweight quality, it has a kind of oxygen in it, which is not to say it's emotionally shallow. We've had to get the brightly coloured wrapping paper right, because what's underneath is not so sweet."
- Bono describing the difference between the "surface" of the songs to "what lies beneath".
U2 only started to make money after the Joshua Tree in 1987, they were already more than 10 years playing as a band then.