Of course, the chef can customize the menu. In fact, many high-end restaurants or private chefs will customize the menu according to customers' needs and tastes. This way can ensure customers' satisfaction, because the dishes on the menu are selected according to their preferences and needs. However, in some cases, the chef's customized menu may not be the best choice:

1. Cost problem: Customizing the menu may lead to higher cost, because the chef needs to prepare ingredients for each customer and cook separately. This may affect the profit and operation of the restaurant.

2. Time problem: chefs need to spend a lot of time customizing menus for customers, which may affect the speed at which they provide services to other customers. In addition, if the customer has special requirements for the menu, the chef may need to adjust it many times, which will consume more time.

3. Variety of dishes: Let the chef customize the menu, which may lead to the dishes being too single to meet the needs of different customers. A successful restaurant should provide a variety of dishes to meet the tastes of different customers.

4. Chef's skill limit: Although chefs usually have high cooking skills, they may not have enough experience or knowledge to meet all customers' needs. In this case, the restaurant may need to hire other professional chefs to ensure the quality of the dishes.

In a word, letting the chef customize the menu can meet the individual needs of customers, but it may also bring problems such as cost, time, variety of dishes, skill restrictions and so on. Therefore, restaurants need to weigh the pros and cons and decide whether to adopt this model according to the specific situation.