I heard this great quote once, don't know who it's by, but it goes "art is never finished, it's always abandoned". I like the sound of that. And I think for me, a song feels finished if I've played it in public a number of times and don't feel the need to change any of it. I'm still tweaking old songs, putting new solos in, taking verses out, rewriting choruses. I find rewriting the lyrics harder though, its so much more tempting to scrap a song than rewrite lyrics. I'm really bad at choruses and I've got one in particular that I cringe at every time I sing it.

Rewriting lyrics is a near impossibility for me. Especially if the song has had time to settle. Recapturing the spirit of the song always seems to elude me.

I like the quote though - think I'm going to remember that.

i write rap, so i tend to focus on lyrics only. i find i have to write a song in one block, then come back later and tweak lyrics here and there, adding new ones in where needed. then i rehearse to make sure its all in rhythym, and voila!, bobs ur uncle

Unfinished songs seem to be par for the course. But it depends how prolific you are as to whether or not it's important.
When I first stared writing, every note was precious. Every phrase had to be used as I never knew if there were any more coming. But as I realised the "well of inspiration" might not be as shallow as I thought, some ideas which didn't come together quickly, I realised could be left behind.
I still revisit them every so often and occasionally they pop into my head dragging the  "missing" piece with them.  Those are joyful days.
But sometimes I don't think any of my songs will ever be finished, but the law of diminishing returns kicks in.
At some point you just have to say that will do, and leave everything else up to whoever is playing them. Their interpretation will probably be slightly different from the original idea. Even the author, playing the song a year later, will probably play it slightly differently. 

Mihkay

I sometimes think writing songs is like raising kids, when they are young and you have them to yourself you can mould them and shape them and help them become as great as they can be but as soon as they go out into the big world they are not yours alone anymore and if you try to interfere you could end up damaging them. As soon as other people hear a song it stops being "your" song and starts being their song as well and if you start trying to change it you can ruin it for others. I know a song is finished when i am happy for others to listen to it.
Does that make any sense? or am i just odd?
Cheers!
Liam.

makes sense to me

I'd be happy if I could get past the first bar without saying this is bollocks lol

Id be happy if i could get past the first bar without going in for a couple pints and a few rum chasers lol!
liam.

I always wanted to build a bar in my house

or a studio in my bar

i forgot