I thought Promethius was a fairly interesting movie by the time that you came to an end. You had to sit there and think about the beginning and the end, and how the next episode will tie up the entire story.
Yes, that was probably part of the problem though, it was a thinking man’s movie, but a lot of the audience heard “Alien prequel” and wanted a sci-fi action flick. Instead, you got Blade Runner’s subtle philosophical dillemmas mixed with Alien’s undercurrent of menace, and not so much in the way of action.