I've often thought that many songs are made by a single good line.
I think Coldplay's 'Yellow' is a great example of this. The subject is a girl, and it's a love song. If ever there was a more tilled field in the annals of poetic inspiration, I don't know what it would be. It's damn hard to say anything original about love. Most of it is pure boilerplate, too:
'Look at the stars.
Look how they shine for you,
And all the things you do.
Yeah they were all yellow.'
Not very inspiring stuff.
But there, right in the middle, is a line that always stuck with me:
'For you I'd bleed myself dry,
For you I'd bleed myself dry.'
It works so well, for many reasons.
They say it twice, with the pause and drop in the instrumentation before the repetition to make sure you pay attention. Then the great guitar riff comes in powerfully. But that's it -it's never uttered again, even though it's clear that the whole song is building to that point. The worst thing you can do with a good idea is bash the audience over the head with it by repeating it over and over.
I think it's the most interesting sentiment about love that I can recall being said in the last 10 years.