It is very hard to be objective about one's work. There is too much emotion and too much of "I love this picture" in the way.
That is why it is important to do two things:
1. Ask for feedback from those who you trust to give you genuine and honest feedback. Many will tell you their emotion or be nice to you. Artistic critique is meant to be brutally honest. One does not grow without honest feedback. I can tell you that it is remarkably productive and brutally painful. We all think we are the best thing since sliced bread, but until we really get to be the best thing since sliced bread, it's best to remember our place in the universe.
2. Give it some time. My experience has been that the longer I wait after capturing an image, the more objective I can be. Even at this stage of the game I still rush back to the studio to see what my images look like, because I don't look very much at my images when I am on a photo op. Yet I have found that as I wait longer to evaluate the images, fewer and fewer of them seem to be keepers worth the effort to take time to deeply process. Take your time. I have listened to other photographers who wait weeks to review their images from a photo op, so they can be more "objective" about their images.
Study and critique of one's work eventually leads to a more clear assessment of one's work.
Take your time.
Accept genuine critical feedback.
Learn to see yourself more clearly. It is hard and takes more time than you want. But it will be worth it.