Sorry, I follow too many people and needed to unfollow those who didn't follow me. I will follow you again.
Cars with engines have internal combustion that needs to be exhausted. That makes noise. Manufacturers spend money to make them quiet with exhaust systems. This reduces power, adds weight, and reduces usable space. Manufacturers of electric cars don't need to add an exhaust system.
Electric cars don't make the noise in the first place because they don't use internal combustion. Mechanical energy in electric cars is created by electromagnets. Electromagnets will attract or pull depending on direction of electricity. That process doesn't create noise.