The main reason the ESA stops working on the OEM shocks is due to the fact that the small electric servo motor that adjust the damping needle is position right at the bottom of the shock, in the alloy mount.
The wiring enters the lower mount through a plastic plug, but this does not seal very well, and with all the spray from the rear wheel right next to it, the water soon gets past the O ring and then capillary action draws it up into the motor and causes it to seize.
We have seen many of these when replacing the OEM shocks with the Tractive ESA dampers.
The Tractive dampers have the motor positioned high up inside the shock, well away from water ingress, so preventing this problem,