This is an age old debate. You’re not supposed to worry about grades but everyone does. In primary my onwing kept telling me I was doing well and I felt pretty good about how I was performing. At the end of contacts I compared grades with my roommates and realized I was not at all on track to select what I wanted. I worked a lot harder and by crushing instrument sims I wound up with jet grades.
You’re supposed to always give 100% but it’s not that realistic. It’s human nature to wonder how you’re doing compared to others in a competitive environment.