One problem is that your plates get very old and beat up. My plates are 30 years old and barely legible. (Actually "plate" since it dates back to the era when the state only used one plate on the rear, no front plate). And, they are a different color than the newer plates.
Most states REQUIRE you to get new plates when they issue new plates the next time you register the vehicle.
In NH…back in the late 80’s they reissued plates 3 times in a 4 year period. What a pain.