A battery electric vehicle (BEV) needs much, much less maintenance. Most research and real-world experience puts servicing and maintenance costs to be 30-50% cheaper than running an ICE vehicle.
Fewer moving parts means there's less to go wrong. The electrical drivetrain is simpler than its' combustion car equivalent, which has as many as 10x the number of moving parts. All of these experience wear and tear and need to be maintained. EVs also do not need such sophisticated cooling, fuelling and exhaust gases systems (no expensive rare-earth mineral catalytic converters!). There are no oil changes required, no spark plugs and no complicated turbochargers to maintain.
Clutches based on friction do not exist and brake pads are used less due to 'one pedal' regenerative braking, which uses the electric motor to slow the car, not the brake pads.
In the first two years of an electric vehicle's life you may only have one service. You will however need to have those special mileage services to maintain the manufacturer's warranty. You'll also need an MOT after the third year each year.