A good action scene can help further the plot, or be the final culmination of events occurring in the movie. For example, the space battle in Nemesis had a purpose and was part of the story. The dune buggy chase just felt tacked on. Literally, it seemed like the writer just thought: "Data picks up B4's head....and THEN DUNE BUGGIES." It's just so non-sequitur and doesn't add anything to the movie. Note: The holodeck scene in First Contact was pretty pointless too: but it was at least a nice Dixon Hill homage for TNG fans to enjoy.