I need to see if I'm progressing. If I stop progressing, I shouldn't waste my dohai's time in the dojo.
Please also note I don't refer only to technique.
No offence - but I don't agree. Nobody can expect you to progress all the time. What would be a waste of your dohai's time would be if you don't do you best. Another aspect is that as you advance in rank, gradings will be further apart so you will have to rely on your own perception of your progressions rather than a senseis accept through gradings.
All the best