I do keep a backup of every picture that I capture via my camera. I love to take 1000 pics of some random thing from different angles. That leaves me with hell of a choices. I have options to use any one of them. I edit the one I love & keep the rest of the pics stored in cloud. See, the best thing about the cloud storage is they are free & can be accessed from anywhere. Well...if you find yourself out of memory in your cloud storage space, take a new account. I think sky drive comes with 15 gb of free space, same is with google drive or dropbox or etcetra etcetra etcetra. So, I recommend you to keep a backup of all photos. Photography is not about which pic you love...it's about which pic others love. You may love a snap that you captured with lot of efforts. But sometimes it may look like shit to someone else. Taste is different for everyone. who knows one day some one will say to you that the pic that you hate the most is the pic that he/she loves the most. Gracias.
I suggest you to make multiple directories based on the year or month the pics are taken. Store pics in 'em.