HCD.18:3 - Forces

• A reusable profile saves effort, but a fixed quality list can miss a task absent from the material itself.
• Shared observations can support several properties, while those properties require different repairs.
• A correct first answer can come from the material, prior expertise, or an available helper; the evaluation must distinguish those contributions when they change reliance.
• More detail can clarify a distinction or obstruct the next action. The property concerns support for the use, not volume.
• A usable ordinal judgement can guide repair without pretending to measure equal intervals or predict learning.
• A demanding task can reveal useful learning work or a missing prerequisite. Immediate ease cannot decide between them.