Whenever you install a screw, first turn the screw counter-clockwise (in the “loosey” direction) to “seat” the screw.

Turn slowly until you feel the screw level off and sink slightly, then stop.

Now it's safe to tighten the screw.

A properly installed screw will turn easily until it's fully tight.

An improperly threaded screw gets increasingly difficult to tighten—because the misaligned threads are cutting across the threads in the screw hole, causing permanent damage. This is known as "cross-threading."

If your screw doesn't tighten easily, back off and carefully re-seat it, and try again.