I always find myself sitting at my Macbook going back and revisiting old Lightroom catalogs. I've found that it is an important part of my learning as a up and coming photographer. You get to see mistakes made while shooting, and the direct results of that mistake, without a looming deadline over your head.
Working as a music photographer with a tight turn around time, and having a small amount of images due for publish, it is easy to look over good images, because you are looking for the images that best represent the story of the event, not your artistic interpretation of it. Not every good image is suitable to send over to the publication, but they are all great in their own right.
Recently, I found myself going through some photos from Paradise Fears, Against The Current, Matisyahu, and Chromeo, and I found some images I passed over on my first run through. Also, the more you shoot, the more your style changes, so I find that it's a good idea to go back, and re-edit files to fit your current and more refined style and photographic identity.