Lucas has contradicted himself so many times on this issue I don't even pay attention to him anymore... Regardless I don't believe it was ever his intention to make more than one movie. Star Wars was going to just be the fourth episode in a Saturday Matinee serial, with the beginning and end not being shown. When Star Wars was a success he got money hungry and decided to finish the Luke story. Then when that was a success he got more money hungry and decided to turn the backstory he had written for the movies into a trilogy of its own, the Anakin story. (To make money). Now, after the PT has earned his loads and loads of money, he's doing a tv series. (Which in turn will bring him more money... go figure). To make another sequel trilogy would be nonsensical because the Skywalker story is over. (No really, it's over). And we all know how much sense Lucas has these days (little to none), so another trilogy wouldn't surprise me. After all, it would bring this already money-laden man more money... which is what we all want.
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