Let a domain owner review the selected promise without auditing the machinery. Let engineers follow the same names into compatible constituents, successors, actual bindings and effects. Each step inward must answer a relevant question while preserving the meaning of the wider view.
Why: a contract that only its author can reconstruct makes that author a permanent part of the system. Comments and diagrams cannot rescue executable relationships that contradict their readable promise.
Consequence: roots and composition points select realizations and bind work; they should not become global service locators. Source layout helps navigation but is not the whole story. A large implementation diagram does not become a business contract by being placed at the root.
Parameterization should express meaningful choices and admissible combinations. Associated types, data-bearing collaborators, concrete carriers and ordinary values have different jobs. Consumers should not have to restate hidden concrete types to follow a declared successor relationship.