Why Does Lancelot Say That He Is Not Worthy To Draw The Sword From The Stone?

Only the true king of England could draw the sword from the stone, which is one reason he couldn't. The other had something to do with a dishonour Lancelot had brought on himself, also legends refer to him as being homosexual and ugly etc. which made him an unworthy king. If you read the Arthurian legends its in there somewhere. As a reader of Arthurian legends, this view is the expressed belief of author's and poets who created the fictional character of Lancelot.