Pre mortem quick

It is DATE. The plan below failed. Not partially, it failed.

Plan: WHAT IT IS.
Success was supposed to be: WHAT.

Write the five most likely stories of how that happened. One paragraph
each, in the past tense, as if reporting it afterwards.

Order them by likelihood, and say what makes each one likely rather
than merely possible.

Then for each story, three lines.

Earliest visible signal. The first thing anyone could have noticed, and
roughly when relative to the deadline.
Who would have seen it first. A role, not a name.
Cheapest action today. What I could do this week that makes this story
less likely or easier to catch.

Then close with one section: the failure nobody is watching. Of the
five, which one has no owner, no signal in any existing report, and no
regular meeting where it would come up.

Realistic causes only. Ordinary ones. A key person leaves, an agreement
was assumed rather than confirmed, the data was worse than anyone
looked at, two teams read the same sentence differently.