basis, below:

*** DefaultLifecycleExecutor

  When binding goals to the project's configured lifecycle, each mojo
  descriptor should declare whether it requires online/offline status.
  This value should be a java.lang.Boolean, so it can implement 3VL
  (three value logic: yes, no, don't-care). The requiresOnline
  field in the mojo descriptor has the following semantics:

  [true] Online status is required for this mojo to function