When a complex task remains only in conversation, people may have a different picture of its order. Writing down tasks helps us see what depends on what and where decisions are lacking.
The plan should show the result, the responsibility and the required information. It doesn't have to contain every detail, but it should be clear enough that the team can check what has been completed and what is blocking the continuation.
Such a record should be changed when we learn something new. A perfect plan is not a requirement to start, nor does a large number of items prove the quality of the preparation. A useful plan facilitates work and discussion, with the possibility that the actual situation may differ from the original assumption.
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