Because as you grow as a photographer and maybe a digital artist, these files that you may think are lousy this year, may be something you can actually work with later as your photoshop skills improve. Unfortunately, I had a bad accident 3 yrs into my photography journey, and I lost every single image I took prior to that day. It saddens me greatly, when I think of all the stock images I had and all the images I would be able to work with now. The external backing up system for our treasured images is SO important, I cannot stress that enough.
Here is a prime example of an image that had lousy lighting and colour balance when I took it a few years ago. Now it is fun to see it transform in Photoshop. I used Retouch + "Striped Wallpaper" from the Vintage Texture Set to assist in the edit of this image.