The OEM motors are an assembly of the motor, and the gear drive parts. The motor is awesome, the worst that should happen with that part is the brushes to wear out. I've never worn out a motor in any of my Fords. The only other failure besides the gear pucks etc, has been the steel shaft which the gear spins around. That happened with my last 91 Mark VII, one door had a roughness for a long time, and once I went in to replace the plastic pucks, I noticed the shaft a little loose. I put it together, and it was skipping a bit still. So that assembly was toast, I scrapped it.
The regulator you don't have to mess with, just support the glass not falling when the motor is removed(three bolts). The small cover on the side has tiny screws, take that off and you are into the gears and grease. Clean it all out, the parts, and reinstall the new plastic pieces as needed. Put it back in, and it should be good for another 10-20 years. That will cost you less than the inferior aftermarket(and China junk) parts, and it should be reliable for longer than you own the vehicle after that.
Now some people abuse windows, they run them up and down several times a day, and they blip the buttons constantly to move the glass a couple of inches. If you abuse the parts, no matter what they are, do not be surprised if they last less than half the time as other people experience. I'd had cars that all the windows and door locks had failures. I had to replace all of the pucks, all of the switches, and the door lock actuators, plus rebend some of te rods to the actuators. Abusing parts is not smart, it causes headaches for everyone later who drives the cars. Be easy with those buttons, the switches are very fragile.