Definition of motor: Device that converts electrical or other energy into mechanical energy or imparts motion.
The advisers that talk about motor inside a cartridge have no idea what is it all about.
The cartridge (in your case MC type) is very simple devise (by design) and very complex (by execution).
First- the moving part has only one joint (human hand with fingers has 27 joints). The rigidity of a cartridge joint supported by tension cable. The softness of a cartridge joint supported by 1 or 2 dampers. The dampers deterioration causes ALL sonic and physical properties of a cartridge become progressively worse. Different manufacturers using different damper material. They last for 1 to 10 years.
Stylus life is 500-2000 hours. If you play 2 LPs a day average life span of your cartridge is 3/4 - 3 years. There is no magic of having the correct, good sound at all.
You have no doubt that you need to change oil in your car every 3,000 miles and tires every 50,000 miles. Cartridge need to be change every 3 years. If you invest into analog- this should be planned expenses.