How would you answer an interview scenario involving abstraction quality?

For an interview scenario involving abstraction quality, I would first clarify the business goal, scale, constraints, and the failure or quality attribute the interviewer wants to explore. A good abstraction captures a stable capability or policy while hiding volatile details that callers should not depend on. For production, design contracts around caller intent, keep guarantees explicit, and evolve abstractions when consumers repeatedly bypass them. I would then explain the main alternatives and tradeoffs, identify likely failure modes, and describe how I would validate the solution through testing, observability, security controls, and recovery or rollback planning.