So I can't find any posts about this, thought I might start my own to get others experience.
I have a Gen 1 Xiaomi Robot vacuum still going strong after 3+ years use.
We've been in our new place now for 2 years and started noticing after the 1st year some faint tracing of tracks caused by the wheels of the robot along the outer edge of the wall of all carpeted rooms.
It didn't bother us too much, but now another year on they are quite noticeable and I feel this will only become more prominent over time.
So, let's break this down into two parts to see if anyone has advice:
1. Prevention
2. Restoration
Note: Our Vacuum is scheduled to run every morning Mon-Fri.
Steam your carpet.