Big cuts need lead time. When a booking already says a tomahawk for four is wanted, the meat is there in time rather than missing on the night — and that is the one disappointment people tell other people about.
On large tables a deposit is normal and it's self-protection. Twelve people who don't turn up is a lost evening; with a deposit the cancellation comes early enough to sell the table again.
Purchasing hangs off the numbers. Which cuts sell, on which days, in what ratio: without those figures you over-order whatever happened to go well last time, and with meat a bad order is more expensive than in any other category.