The account is filling a calendar, and the calendar runs out
Build capacity is fixed by crews and subcontractors, so there is a point in the season where more demand stops being useful.
A pool builder can only start so many projects. Once the schedule is committed, an additional sale is not additional revenue this year, it is a longer wait for somebody who was told a date.
That makes pacing a genuine strategic decision rather than a budget detail. Accounts that run at a constant level all year tend to overspend into a full schedule and underspend during the planning window when the decisions are actually made.
The shape that usually works pushes hard through the planning season, eases once the build calendar is committed, and keeps a smaller presence running for the following year's early researchers.
There is a version of this that is worth doing deliberately: continuing to advertise while being honest about the start date. Some customers will happily book for next season, and a builder with a known waiting list is in a stronger position than one discounting to fill next month.
What does not work is filling the calendar quietly and letting the sales process discover it. That is how a customer signs believing one timeline and hears another later.