(click on image to enlarge)
This is a handy trick. If you have put in screws, you have come across this problem. The hole has been enlarged or is stripped and the fastener will no longer tighten. This is especially true in thin paneling or in the situation in the pictures. I had to replace the door hold back on a trailer and there was nothing to tighten to. The factory installer had already stripped the holes and relied on the caulking to hold the original fixture to the door.
Just insert the screw into the stripped hole, slide some tooth picks around the screw and carefully drive the screw home. Use a hand driver or be very careful if using a drill driver so as not to strip it out again. You will be surprised how often this will do the trick!