Retention never comes back on its own

Retention is designed to be forgotten. The triggers that release it, practical completion, making good, the end of the defects period, arrive months or years after the job's team has scattered to other sites, and the payer holding the money has no incentive to volunteer it. So the releases fall due in silence, and the fund sits where it is, job after job.

Per job it looks small; across the jobs you have closed out it compounds into your own money financing someone else's balance sheet. Getting it back is rarely a fight, it is administration nobody owns: the release dates lifted from each contract, tracked to their triggers, applied for when they fall due and chased while chasing is still routine.