Often, as I read the external letters of evaluation written by experts in support of the tenure cases of stellar junior faculty, I wish these young professors knew how highly the senior colleagues thought of their work. Some of these letters are full of genuine praise and admiration.
If you are an academic, it’s likely that you sometimes — perhaps often? — fell insecure about your professional standing. How could you not? Everyone around you is smart and successful, and the competition for funds and top publications is fierce. There is very little, if any, direct affirmation; you only ever get it indirectly through accepted papers, citations, invitations to give talks, or an occasional award. I bet it would feel really good to read, black on white, how much your professional peers and elders admire and respect you.