Measures outlive the conditions that produced them
Bar length is time in force; the marker is where the cause ended; the tail after it is the part nobody forecasts.
A measure’s tail is made of the work done after its launch: contracts rewritten, routes recast, staff assigned, fees collected and a rulebook that now has owners. Ending it requires a decision, while leaving it in place often requires none.
The cause is the event that made action urgent. The mechanism is the auction, waiver, control or premium rule built in answer to it. The event can clear while the mechanism keeps serving a different interest, which is why the original announcement is a poor guide to its withdrawal.
The diversion began as a response to an incident at a passage, but the route remained in place after that stated cause ended. The resulting schedules and operating routines required a fresh choice to restore the old route, not merely the disappearance of the original danger.
The auction answered restricted passage capacity, then became a standing way to allocate scarce transit. Its tail belongs to the mechanism: an established allocation tool can remain in use even when the condition that made rationing urgent has eased.
The emergency import waiver is the lapse counter-example. Its shortage cleared and the waiver expired without renewal, showing that a written end point and an administrator willing to let it work can reconnect withdrawal to the cause.
Name the institution that can end the measure and establish whether anyone there must initiate that decision.
Read the operative text for a sunset, renewal test or automatic lapse rather than relying on the temporary language of the announcement.
Identify the routes, contracts, systems and fee streams built around the measure, then identify who loses when they are unwound.
Treat the end of the stated event as one observation and the withdrawal of the rule as another; they are often different decisions.