A door window may move slowly or stop in mid travel due to a failing power window motor. The affected window may start working again after the motor cools off. Replacing the faulty window motor will commonly correct this concern.Google+
Car Problem Reports
Chevrolet S10 Blazer Power Window Motors May Fail From Overheating
Chevrolet S10 Blazer Problem
Average Mileage: 143,500 mi (120,000 mi - 159,000 mi)
The gearbox lubricant fails: it gets sticky like honey and runs into the motor area literally gumming up the works. Replacing the motor assembly fixes the problem. All four of my windows were affected this way.
It might be possible to fix the motor assembly. The motor looks like it will slide out by bending back two tabs on the housing. The gearbox would have to be cleaned out with solvent and re-lubricated. This might not be worth the trouble since replacement motors are under $50.
Visitor, 1994 Chevrolet S10 Blazer, 159,000 mi
driver side power window stopped working