What an Apron Does That a Tax Does Not
An apron is a payroll threshold that withdraws permissions rather than charging money. Once a team's committed salary sits above it, specific transactions become unavailable at any price. Willingness to pay stops being relevant, because there is nothing to pay for. That is the conceptual break with the tax: a tax says a move is expensive, an apron says the move is not permitted.
The system uses more than one threshold, arranged in tiers, and each higher tier removes more. The lower one strips some of the tools a team uses to add outside talent and narrows how trades can be constructed. The higher one goes further, removing the mechanisms that let a team package contracts together, and reaching past the current roster into future assets by restricting how far ahead the team may trade its draft picks and how those picks are treated. Because the restrictions attach to committed salary, a team can also lock itself into a hard ceiling for an entire year through a single transaction, which is why front offices sequence moves carefully and in a deliberate order.
