In the prequel trilogy of Star Wars (the more recent three), the swordsmanship of the actors is greatvery coordinated and fast. There's lots of aerobatics and fast swordplay; generally impressive (albeit sometimes over-the-top) performances.
But in the original trilogy, Luke Skywalker's swordsmanship appears to be an aimless, desperate swinging motion in nearly every scene. He flails the lightsaber back and forth like a wild boar. It's astounding that Vader didn't quickly put him out of his misery.
Here's what I mean:
Is there some sort of explanation as to why Luke's skills are so poor? Does it have to do with the story element, or is it to do with the film itself?