What is prime cost, and why does it matter more than food cost alone?

Prime cost is food plus labour, read as one number against revenue. The two lines trade against each other — a scratch kitchen runs lower food cost and higher labour, a prep-light concept the reverse — so either can look healthy alone while the sum sinks the model. The published band is 55–62% of revenue; above that, the rest of the business has too little left to live on.

From Restaurant Profit Margins in the UAE: What the Numbers Should Look Like — the full reading, with the method behind this answer.