Not to mention the cost to get it removed if that’s ever needed.

oh in some cases the possible consequences straight up outweigh benefits, so people will just leave them in and are stuck with them permanently:

Barbara Campbell, who received her implant during the clinical trial of the Argus II, did find the bionic vision system useful. As a New York City resident, she used it outside on the busy sidewalks and while taking a subway or bus. “The more I used it, the benefits increased,” she remembers. “I think I was retraining my brain to see stuff.” But in 2013, after four years of regular use, Campbell’s system shut down in the subway station, and despite some repair attempts by Second Sight, never worked again. While she talked with her doctors about having the implant removed, she ultimately decided that the risks of another surgery weren’t worth it. She still has the defunct technology in her left eye.