I saw this on another thread and didn't want to hijack it.The motor assemblies get water in them and the internal drive motors die. They are not repairable and Maytronics actively keeps the internal components off the market. Therefore, after it fails outside of warranty, you are forced to either pay for a very expensive motor assembly replacement or buy a new robot. Motor assemblies right now cost $450 + tax & shipping.
Expect the average life of the unit to be around 5 years.
Is there any periodic maintenance we should do to mitigate this? Like, I try to change the seals on my pump every season.