Have they changed or have I?

At TBU, advanced class require students to write a introductory paper to kick of the class. I am commenting on students work so far in the course for my most advanced class, and I am struck by something. To write up the summaries, I am taking the summaries I wrote last year, and writing over them. What I seem to notice is that I had these very detailed comments to students about their work so far in the class and their introduction papers last year. This year, I find myself struggling to say anything. So, I ask myself, are my students less interesting this year or am I less interested this year. I find myself a bit scared if I am bored with my students already this year.