Interior doors today for the most part are made of Masonite with a cardboard filler. The exterior frame is a solid piece of wood but only a very small amount. Here at this inspection the person that installed the door cut off to much at the bottom and now has no solid wood piece at the bottom of the door. This should have been corrected by adding the piece back or making a piece to fill in at the bottom.

Problems now is that the bottom of the door will warp and as you can see easily moves in and out. Repairs are needed by a qualified person.