Test the second access path before you call a metric unreadable
Three of four "unreadable" metrics were readable through a second access path. Write down which path you tried, and store NULL, never a fake zero.
, 4 min read
I keep a list of surfaces whose numbers I could not read, with a short reason written next to each one. Discourse gives you nothing per post. The comments API has no reaction field. Once a line like that is written down it stops looking like a hypothesis, and nothing in my process ever reopened one.
This week I re-probed four of them and three turned out to be readable.