Main idea

Deciding to work up an opportunity means making a bet: on a theme, on a feature, on an expected impact. That bet is paid for in things given up — you set aside other subjects, other segments, other readings of the same problem. The narrowing of scope is not a limit suffered for lack of time, it is the act of product management itself.

A knowledge tool can support that gesture or contradict it. A bounded space, holding what concerns the opportunity and nothing else, embodies the decision: what is not in it has been set aside, and that choice is readable. A network that links everything to everything does the opposite — it permanently reopens the perimeter you had just closed, and hands back at every consultation the associations you had decided not to make.

The criterion is therefore simple, and it comes before any comparison of features: the note system must reflect the narrowing, not fight it.

Why it matters

This gives a reason to prefer a poor container to a rich one that has nothing to do with simplicity for its own sake. What you lose in connections, you gain in the readability of the choice: a bounded space says what you decided not to look at.

It also guards against a common failing, the continuous widening of a study by the addition of relevant information. Each item is relevant; their sum dissolves the bet that justified the study.

Nuances and limits

A bet can be a bad one, and too closed a perimeter keeps you from noticing: it is often an adjacent element that reveals you framed it wrong.

The narrowing is therefore decided, but it has to be reopened — and nothing in a bounded space says when.

Open questions

• What signal tells you an opportunity's perimeter was badly cut out, rather than simply thin?