1 time is a single publish. It does not mean once a month forever.
Choose 3, 6 or 12 when you want the same task to run again after the first scheduled time. The task stops after that count.
The count
- 1 time: one run
- 3, 6 or 12: that many runs, including the first
- The task returns to scheduled after each run until the count is done
- History keeps one task for the series
Watch the status in History if you are not sure whether another run is still planned.