The mechanism · The redemption · Element
The friction
How difficult redemption is.
The part
What it is
Restrictions, expiry, blackout periods and minimum thresholds all reduce cost and reduce perceived value more.
Each is a decision to make the programme cheaper and less effective, and it should be made knowingly.
The smallest level
The attributes it carries
Each attribute is one of the framework’s shared types. What a date is, and how it is written, is defined once for the whole model — the note here says what it means in this particular place.