According to Lucas, the original “Star Wars” draft had Obi-Wan witnessing the Death Star dogfight, and continuing on into the hypothetical rest of the trilogy. However, faced with the necessity to condense his story, he realized that Kenobi’s arc ended before the final act of the film. Lucas observed:
“In the process of rewriting that script, and thinking of it as only a movie and not a whole trilogy, I decided that Ben Kenobi really didn’t serve any useful function after the point [when] he fights Darth Vader. Although in that draft he continued on through the air battle at the end, and then he continued on through the whole script, the other two stories. But when I took one [story] and I looked at it I said, ‘You know, he just stands around for the last twenty five percent of the film, watching this air battle go on, and he really has no real function, and it’d probably be much more satisfying, powerful, and interesting if he, if Darth Vader were to kill him, or he would go into a different form.’ I made that decision based on just working on ‘Star Wars’ [‘A New Hope’].”