The four settings differ in the degree of how voluntary they are from the user perspective, which affects their constraints. For example, the Older Citizen setting is relatively voluntary for seniors, assistants, and senior centers; the Voting setting has a mandatory accessibility requirement on the provider side, with voluntary participation on the voter side; the Online Assessment and OER settings have mandatory aspects for schools, teachers, testmakers, and students. The Workshop clarified that there may be design implications for different degrees of voluntariness. For example:
- If high completion rate is a goal, a voluntary tool may need to be easier to use and more engaging than a mandatory tool.
- The design of a mandatory tool may require more legal and regulatory analysis and review. For example, a tool used in the voting application setting may need to meet the same accessibility requirements as the voting machines themselves, as well as lead to effective use of the accessibility features of the voting machines.