Why the work is periodic
The expensive parts of revenue operations happen in bursts. Mapping the systems, settling the definitions, joining a new platform — each is a decision followed by a build, and then months where the right amount of attention is considerably less than a full week.
Hiring for the burst means paying for the trough. Hiring nobody means the definitions go stale, the syncs quietly break, and the next burst starts from a map that no longer matches the building.
A retainer is the shape that matches. It is not a discount on a hire and it is not a support contract. It is a standing claim on the judgement, so that the system stays true between the projects.