In classes, I often see photographers who feel they need to be "perfect" and don't like to make mistakes with assignments. I think this will not help a photographer become a better photographer, even though I will hear things like, "I am really serious about this and I want to become better, so I strive to make every assignment perfect." And I will hear photographers trying to do something similar with all of their nature photography. It is like they think mistakes and "failure" somehow dishonor the "perfection" of nature.
We could get into a long philosophical discussion about perfection, but there are some things that are important. First, I don't see any photograph to ever be a failure as long as you learn from it. That goes back to one of the great things I love about digital photography, the LCD review. Even when I am in the field, I look at my images to see both the good and the bad, and I learn from both while I am still shooting. That helps me get better photos as I go.
It is true that the "better" photos usually get more comments from other people, so they stroke the ego, but it is the less than "perfect" photo that often gives more to think about or the instructor to talk about. I don't think anyone needs to feel badly about any photographs. So one was not as successful as the others, so what? It gives a great opportunity to think about new possibilities to correct that challenge.
I mentioned the "perfection" of nature. I often hear that, too, yet nature may be a better model for photographers than that. Nature simply is -- it cannot be perfect because that implies no change, yet nature always changes. Nature has beauty and ugliness, it has elements that can inspire wonder and also disgust. Nature is far too complex to be "perfect" and it is actually in its imperfection that it is able to adapt to changing conditions.
As photographers, we can relax and adapt to conditions, including our "state of photographic mind", as we photograph, and that can lead to better images than stressfully trying for perfection that can never really be achieved.