It is not fun to deal with knobs and pulls with stripped threads so that the knob or pull come off of the drawer or door when grasped, yet it happens frequently.
Many at Instructables have dealt with this often in their time. This is for the person who has the problem, but does not know what to do about it.
Step 1: The problem and one solution
The threads strip out in the first 1/8 inch or so of the threaded post on the backside of the knob or pull. Many simply insert part of a paper matchstick into the hole and twist it back onto the screw. This may last for a very short time, but eventually fails.