Narrow the cone

Play this lesson

A promise for the publisher

A publisher will fund Shard Garden if the studio names a launch date and is never more than 3 months late. Kai's estimate is 12 months, so the worst case the studio can accept is 15.

The cone of uncertainty says how far off a skilled estimate can be at each milestone. When can the studio safely promise?

Try it

Narrow the cone

Tap a milestone to see the real range of a 12-month estimate at that point. Find the first one where even the worst case is 15 months or less.

Try it in the lesson

Quick check

At "Features listed", 12 months really means 8 to 18. Why can the studio not promise yet?

  1. The worst case, 18 months, is 3 months past the promise
  2. The best case, 8 months, is too early
  3. The range is too narrow to trust
Show the answer

The worst case, 18 months, is 3 months past the promise

The publisher's limit is 15 months. Finishing early is never the problem: a promise has to survive the worst case.

What narrowed it

Each milestone is a set of decisions. "Game defined": what Shard Garden is and is not. "Features listed": every feature it will have. "Tech planned": how each one will be built.

Construx calls them approved product definition, requirements complete, and detailed technical requirements complete. Nobody waits for a milestone. The team does the work that removes unknowns.

Quick check

The cone narrows by itself as the months pass, even if the team makes no decisions.

Show the answer

False

Construx: "The Cone narrows only as you make decisions that eliminate variability." A project that never decides stays as uncertain as on day one.

Promise a range, then a date

Before "Tech planned", the studio shares a range and what it depends on: "6 to 24 months now. We can commit to a month once the tech plan is done."

The publisher sees which choices move the date, and that the studio is not hiding anything.

Pick the promise

Email from the publisher
The game is defined, great. We need a launch month today, before you list the features.

What should Kai reply?

  1. Today we can honestly say 6 to 24 months. We will commit to a month once the tech plan is done.
  2. Promise 12 months and hope it works out
  3. Promise 48 months, to be safe
Show the answer

Today we can honestly say 6 to 24 months. We will commit to a month once the tech plan is done.

Once the game is defined, the cone runs from 0.5 to 2 times 12 months. Promising 12 now risks being a year late, and 48 months would lose the deal for no reason.

On the studio board

The studio adds a second decision to the board:

Launch promise: only from "Tech planned", with the worst case at most 3 months past the date.

Bolt says: Next: who pays for 12 months of work, and what they get for it.

Fact-checked 12 October 2026