The difficult detail deserves attention when the simple account depends on ignoring it.

Not every complication is worth chasing. The ones that matter are those a tidy explanation has to leave out in order to stay tidy, since that is exactly where the account is doing work it has not earned. A story that survives the awkward fact is stronger for including it. A story that requires the fact to be dropped is telling you something about itself.

When you notice a detail that spoils a clean explanation, sit with it before setting it aside. Ask what would have to be true for both it and the explanation to hold, and see whether an answer exists.