Here is a challenge for you:

1. Pick an unedited photo of yours that you really like
2. Set a timer for 1 hour
3. Spend that hour analysing your photo for flaws and improvement opportunities, correcting all of them

If you run out of ideas on what to improve before the alarm rings, you know need to do some more studying and research on this subject... :)

It sounds really tough (1 hour is a lot), but its amazing what sometimes happens when you stare at a photo for a much longer time. You constantly notice new things. It's a very good exercise...