Just like the example of American donuts, the sales volume of traditional donuts is already very low. Compared with other industries, food is a necessity (with higher demand rigidity), so the mature stage of the life cycle of the general food industry will be very long, and there will be no obvious decline like other industries. We generally don&;t regard doughnuts as a separate industry, but form a baking industry with similar products. From the perspective of the industry as a whole (especially in western countries), perfect substitutes is less likely to appear. However, the development of this industry may be affected by factors such as population and living habits. From a personal point of view, this sub-sector is still relatively small, especially for the market, which is far from mature. If you remember correctly, it has just become popular in recent years. It is difficult for you to find a company that can be used as an analogy, but his risk is also here. Because it is too small, his demand may be established, and there is an upper limit. You need to consider his sales volume and potential profit in the region. It is suggested to start from the classical economic point of view. This idea is also used to make your decision on whether it is better to invest in traditional catering or online celebrity catering.