Our house came with an old solid wood front door that even after many years of shaving off the edge likes to stick when the wet winter weather arrives.
So the vertical side edge with the lock (opposite the hinge side) is closer to the Jamb at the top. So its the usual Sagging situation.
To my mind if i would sink the top hinge further into the jamb it would remedy this situation.
This youtube shows someone fixing this situation using a small coin placed between the door and the top hinge.
The youtube title is:
"how to adjust a door with a penny, no need to use a door planer".
Would someone more clever than myself be able to explain the mechanics of how this works please.