HCD.28:1 - Problem Frame

A prospective audience can be described before any member is known. That permits useful design: an author can qualify a task, compare explanations, prepare a practice route and estimate support. It does not permit assigning a personal diagnosis or programme to every member.

Parts may look adequate separately and still fail together. A lesson explains a calculation while the later task requires choosing the model. A task elicits a difficult question after the mentor has left. A group produces a strong report while several participants never make the judgement the product promises to teach. An attractive self-service price excludes the time needed to read, practise, check and repair.

The author needs enough subject competence, or access to a qualified subject contributor, to distinguish a pedagogical choice from an unresolved domain question. The intended reader of this pattern can design tasks and support, compare resource demands and recognize the limits of that subject access. HCD supplies no engineering, clinical or other professional authority by itself.