Supportability is the ability of the system to provide information helpful for identifying and resolving issues when it fails to work correctly.
Points to be considered:
Health Check End Points
Logging and Monitoring
Testability
Testability is a measure of how easy it is to create test criteria for the system and its components, and to execute these tests in order to determine if the criteria are met.
Points to be considered:
Automation testing
Test Driven Development (TDD) or Acceptance Test Driven Development (ATDD).
Service Virtualization
Usability
Usability defines how well the application meets the requirements of the user and consumer by being intuitive, easy to localize and globalize, providing good access for disabled users, and resulting in a good overall user experience.
Points to be considered:
Who will be using the system and how?
Design solution, system, and UI by considering end user requirements as well as user feasibility.