Sometimes, it is very weird why Gradle keeps telling that a job is UP-TO-DATE, even when the output directory do not exist. In this case, run gradle with the -i option, as this gives information why a task is skipped, e.g. like this:

Run gradle -i for debugging why a task is skipped:

gradlew -iPutting task artifact state for task ':appweb3-gui-web:combinejsForMe' into context took 0.0 secs.
Skipping task ':appweb3-gui-web:combinejsForMe' as it has no source files and no previous output files.
:appweb3-gui-web:combinejsForMe UP-TO-DATE