Yep "breakage" is the % of reward value that goes unclaimed. Once a user claims their rewards to their own self-custody the business will of course no longer be able to do anything about it, but up until that point any unclaimed value could always be rolled over or returned back to their reward budget. One of the businesses we're talking to about this even wants to take a portion of the breakage and use it to establish a corporate treasury position in bitcoin!