I think maven did not push incremental builds because there was not a big need.

Most people code Java in an IDE. Both Idea and Eclipse do incremental builds inside the IDE. So as you are coding, you are incremental building.

Every place I have used maven, maven was used for the build server and the final release. Spinning on a webpage changing some code? You are using your IDE for that.

(Now scala is a little bit different, so we have SBT with incremental support as a pretty ground level thing)