The most important thing in the restaurant business is to have a strong concept. Without a strong concept, you will disappoint your customers, waste money, buy the wrong size tables, and waste space.
The menu, staff service level, staff uniforms, restaurant décor, table height, chair size, chair type, service style, exterior, interior and menu, all revolve around the concept.
The concept is also the basis for marketing the restaurant. The way of marketing a fine dining restaurant is completely different from the way of marketing a takeaway restaurant.