[jmacusa]

That sir is the key to this whole thing. Oswald was a Marine. And you do not become a Marine unless you qualify as a marksman. Oliver Stone knew that when he made this film and he knows that today. He completely changed that key element in the movie. No recruit shoots "Maggie's Drawers' on a Marine rifle range and goes on to earn the Globe And Anchor.

[DesertRhino]

The quote was that his buddies said he wasn’t very good on the range and shot maggies drawers. The movie quote doesn’t say he failed to qual.
Getting the toilet seat “marksman” badge is looked on as a failure by other Marines, but its a qual.