One of the most toxic feelings that a photographer (or human being) is to feel envy. Apparently envy is a trait that is deeply embedded in us, even as babies. But why is it that we feel envy, what are we envious about, and what can we do about it?
Over the years I've tried to get better about reflecting on my work and life at the end of each year. Sure lots of people will claim to do this, but that usually just boils down to reviewing their Facebook page for a quick ego boost.
I'm talking about going in-depth. Go pull up those photos you loved at the beginning of the year and try looking at them again with a newly critical eye, do it when you're free of the fresh-born-photo sentimentality all photographer's (and really artists in general) suffer from. Try to figure out what went wrong in your failed work and what went right (purposefully or accidental) in the work that turned out good. Regardless of the conclusions you arrive at I can guarantee you'll be a better photographer as a result.