I think most professional musicians and artists can relate to the following story. I have countless times, from the start of my career until the present day, worked on a body of work, a whole album, and I have tracks which I personally feel are the strongest by far, and then I have some left over bits and bobs which I've wanted to throw in the trash. And then I've gone and played that bunch of left over music to people and everybody latches onto some strange idea I was going to bin, or a strange track on an album which I didn't want to be on there in the first place.
It's common place this scenario and I've learn to accept that there is a huge element of unpredictability to which ideas penetrate the collective consciousness and stick. Imagine if I'd gone and thrown those ideas I doubted in the trash? what a waste it wouldn't been. And thus in order not to miss out on those unpredictable hits you need to learn to nurture all the ideas you are working on, even if you don't necessary feel it's the perfect song or tune, it might in the end just turn out to be the one which will break you, as has so often proven to be the case with myself and many others I know.
So in line with this strange quirk of nature I encourage you to adopt a much more laid back approach when crafting your music. And learn to never doubt your music, riffs, ideas or throw stuff away; keep each idea and learn to develop all of them. This approach is the opposite to perfectionism and really frees you up to greater potential of generating amazing original music.
CONCLUSION: THE IMPORTANCE OF FINISHING MUSIC
Once you realise that you can't always be sure which of your ideas might stand out and which might not, it then becomes of paramount importance to realise that you must aim to finish most or all your ideas, as you never know which ones might inevitably turn out to be fantastic.