Why does my HBS 3 sync job transfer all files each time it runs instead of sync incrementally?

Whether a sync job syncs incrementally or transfers all files each time it runs depends on whether the setting 'Check file contents' is enabled and also whether you have an RTRR or Rsync sync job. If 'Check file contents' is enabled, HBS 3 compares the actual data of each file, which can lead to a full transfer if any differences are detected.