Celebrity memoirs in the United States cluster in the autumn, and the timing follows the way the books are actually bought. Most are purchased as gifts rather than for the buyer.
The book is bought for someone else
A recognizable name solves the gift problem, because the buyer does not need to know the recipient's reading taste, only who they like.
That makes the category behave like general merchandise, selling through department stores, warehouse clubs and general retailers alongside conventional bookstores.
Those retailers plan their holiday assortments months ahead, so a title must exist and be scheduled in time to be included.
The hardcover format suits the occasion
A gift is expected to look substantial, and a hardcover with photographs and a designed jacket presents better than a paperback at the same price.
Publishers produce these editions accordingly, with production values aimed at how the book appears when handed over rather than how it reads.
The paperback then follows the next year for readers who were not buying a present.
Promotion is concentrated in the same weeks
Television appearances, magazine coverage and podcast interviews are booked far in advance, and the autumn slots are the most valuable of the year.
A celebrity memoir competes for those bookings against films, albums and other books, which means the publication date is set around securing them.
A book released outside that window can still get coverage, but not the concentrated burst that drives a gift-season sale.
Ghostwriting makes the schedule achievable
Most of these books are written with a collaborator, because the subject has neither the time nor usually the training to produce a manuscript on a publishing deadline.
The collaborator interviews extensively, drafts, and revises with the subject, which compresses a process that would otherwise take years.
Credit arrangements vary, and the practice is widely understood inside the industry even where the cover shows a single name.
The window is unforgiving
Because so much depends on a few weeks, a delay can push a title into a season with no gift demand and no available promotion.
Publishers therefore hold firm on delivery dates for these books more than for almost anything else on the list.
The rigidity of the calendar, rather than any editorial judgment, is what determines when most celebrity lives reach print.