...
Task work
By default, task work equals and task duration . Change it, if on a certain day, you plan to work on a task less time than task duration hasare equal. Set task duration and change the task work to distribute total task work per days, on Edit dialog.
For instance, task work is 1 day but you plan to work on the task for 2h per day. In such case, you’ll edit the task duration by inserting “4d” into Duration field:
...
With other words, you are spreading the 1 day of work on the task per 4 days which results in 2 hours of work per day for 4 days.
...
Task duration
Duration becomes work logged + remaining, where remaining is taken from the Jira issue. Each time you log work, Jira asks for remaining time. Task having remaining time 0m is treated as completed.
...