Definition

The intermediate conditions that must hold between a transition's starting state and its resulting state when the gap between them can't close in one move.

Why sub-conditions exist

Some transitions move directly from start to finish — flip a switch, the light is on. Most don't. When the resulting state requires conditions that the starting state doesn't already supply, the parent transition needs intermediate conditions to bridge the gap. Those intermediates are sub-conditions: states that must hold somewhere between the start and the end for the parent's completion criteria to become satisfiable.

Sub-conditions sit on the parent's critical route. The critical-route construction method — for each completion criterion, trace what causes it back to the starting conditions — produces sub-conditions as the intermediate causal stepping stones along the way.

Sub-conditions vs. sub-transitions

Sub-conditions are paired with sub-transitions but structurally distinct. Sub-conditions are the intermediate states the parent transition requires; sub-transitions are the activities that produce them. A sub-condition is a state of the world; a sub-transition is a happening that brings that state about.

Dependency relations and structural patterns hang off sub-conditions, not sub-transitions. The causal sequencing of a critical route is determined by which sub-conditions require which other sub-conditions to already hold. Sibling independence — siblings that can be fully independent of each other while still collectively ratifying the parent-scale claim — is a relation between sub-conditions. Two sub-transitions presented in sequence may or may not carry structural dependency between them; whether they do is determined by what state each requires as input.

Example

Between a signup cohort's entry point and first paid conversion, the gap rarely closes in one move. A user can't sign up and immediately pay — intermediate conditions need to hold first. A typical critical route here has sub-conditions like:

• The user has formed a credible understanding of what the offering does for their intent
• The user has experienced the offering performing against their intent at least once (a value milestone instance)
• The user has encountered the conversion ask at a moment their pursuit and the offering's terms line up

Each names a state of the user. The sub-transitions that produce them — onboarding sequences, first-action use, paywall presentation — are what the team builds. The sub-conditions are what those builds have to put in place for the parent transition's resulting state to become reachable.

See also

• Scope-translation