The progress circle becomes "useless"/"pointless" after some classes. Let me give you an example:
Let's assume I add 10 new words in my vocabulary each class.
- After the first class 10 words represent each 10% and my progress bar moves from 0-100
- After 10 classes I have 90 words already and move from 90-100%, so each word represents 1%
- With 100 classes my range is 990-1000 words and the progress just shows progress in the 0.1% range
It would IMHO make more sense to just display the progress of something like
- the progress in the last 10 classes
- or the last 4 weeks
to display the recent progress instead of the all time progress.
This would also avoid issues like here, where some corrupted data block the progress circle..
As you can see in my case, the expressiveness is very low for long time students: