Reality has more detail than any plan can hold
💎CORE ARGUMENT
A plan is a description, and a description is always shorter than the thing. That gap is no flaw in planning. But the missing detail is where the trouble sits, and I cannot see it from where I am standing when I plan.
Our launch plan was good. A second load test passed on 3 March, there was a dry run on the 5th and a pre-mortem on the 10th, where we wrote down everything that might go wrong. At 21:00 on the 11th we switched on. At 23:40 the duplicate exceptions started. We rolled auto-triage back at 02:40 and had the all clear at 03:15.
The bug lived in a detail the plan had one line for. Nobody had been careless about it. From the height at which plans are written, that detail looked like a single thing, and it turned out to be several. We learned that by being inside it, at midnight.
That is the general shape. Every step that reads as one line contains its own smaller steps, and those contain theirs. Most of them work. I cannot know in advance which will not, because the ones I can foresee are the ones already in the plan.
Three things follow. A plan's accuracy is limited by how close its author has stood to the work. The cheapest way to find the detail is to touch the real thing early and small. And the missing detail only ever adds time, which is why this note supports 💎 Late projects are late by a multiple and not by a margin.
The same thing happened with the cable tray for the desk. I ordered one from a drawing, at the wrong width, and it took three weeks to get right.
Where I might be wrong. This is a comfortable lesson to draw from my own launch. Reality is detailed shades easily into nobody could have known, and somebody could have. Nadia thought the first load test was too gentle back in January, and I let a compromise stand. Some of the detail was visible to a person standing closer than I was.
So the honest version is narrower. A plan cannot hold all the detail, and I should ask the people nearest the work what it leaves out before I call the rest unforeseeable.
🧱BUILT FROM
🌍WHY IT MATTERS
- I ask of any plan: who wrote this line, and have they done the thing it describes?
- Every launch plan now has a rehearsed way back and a named person to take it.
- I trust a small real run over a large careful document.
Where I saw it: 📂 Exceptions Inbox general availability · 🏡 Flat on Lindgate Street · 📂 Home office in the spare room
☑️NEXT STEPS
- Write the incident timeline with Priya, 23:40 to 03:15
- Add a rehearsed rollback to the launch checklist
- Before the next go or no-go, ask QA what the plan compresses
📖 Salvatier on the detail in reality: the detail in ordinary things is close to endless and cannot be seen until you are doing them. After that it is impossible not to see.
💎 Late projects are late by a multiple and not by a margin: unseen detail can only make a project longer, so the error runs one way. 💎 I can listen to a system but I cannot control it: the system would not tell me where the bug was however good the plan, and I had to watch it and respond.
Any step in a plan compresses many smaller steps into a phrase. The compression hides exactly the details nobody has met yet, and those are the ones that fail. They only show on contact, so the plan is most confident where it knows least.
The pre-mortem did catch things, and so did the second load test. Without the plan the rollback would not have been ready at 02:40. Planning is not shown to be useless here. Its job turns out to be preparing the response, since it cannot predict the event.
Written up for readers as 📝 Issue 35 - What a launch teaches that a plan cannot, two days after. Written up for us, without blame, in 📌 Write up the launch incident with Priya.