Three task states are enough for many personal workflows when each state has a clear meaning. Extra labels rarely help if the title and completion rule remain vague.
To Do means ready but not started
A To Do item should describe an executable next action. It may be important or scheduled, but no active work has begun. If it is waiting for access, material, or another person, rewrite the next action or keep that condition in the task notes instead of pretending it is underway.
Doing means attention is committed
Move a task to Doing when you have started producing or checking its result. Keep the number of simultaneous Doing items small enough to represent reality. Switching windows is not itself progress; the task remains Doing only while its outcome is still being worked.
Done means the finish rule passed
Before marking Done, compare the result with the task’s observable completion condition: the file was exported, the message was sent, or the link was verified. If review reveals a problem, return the item to To Do and rewrite the remaining action. Do not invent a fourth “almost done” state when a concrete follow-up describes the truth.
Wallo cycles to-dos through To Do, Doing, and Completed. Completing every to-do does not create a separate completed-goal state. Goal visibility can change when the “hide goals without unfinished to-dos” filter is active, which is a view rule rather than archival.