Xu Zhiming sees more the development space of Kuai Shubao in the next few years. He kept saying, if all could be like the first few days of "Jobs's Biography" coming to market, delivering 700 copies every day, then there would definitely be a profit. But in Liu Yuan's eyes this was an unrealistic thing, "I once also thought that if we could reach 20 million yuan in sales, the situation might improve, but the result was worse." From an economic perspective, e-commerce and traditional retail are the same, under the premise of controllable costs, there will certainly be a critical point, after which profits will be realized. And the scale effect in the traditional sense can also be achieved on the Internet, which is exactly the basis of the long tail theory, and also why all B2C sites put user scale development as the top priority. Former General Manager of Baidu Social Networking Division, IT famous blogger Mai Tian once compared the "eGuo model" and the "long tail model", in his view both directly reach end users, both are micro-income, and both hope to achieve scale effects. But why did Google's "long tail theory" succeed while the "eGuo model" eventually failed? "The Internet as a new tool actually breaks through the limit of transaction costs of traditional tools, overall reduces transaction costs. Under this new equilibrium condition, the long tail theory can therefore stand, namely the Internet tool makes the micro-income under the long tail mode greater than the micro-expense, so the accumulated micro-profit can generate huge profits. However, eGuo essentially did not use the Internet, it appears to be a website, but its main cost part logistics cannot be completed by the Internet in any way, so it is fundamentally impossible to reduce the equilibrium of transaction costs and income, the accumulated micro-losses finally become big losses." Mai Tian explained. But short-distance B2C still must follow the line of thinking of the long tail theory, its product nature determines this point. "Labor costs are there, without a high enough purchase frequency, logistics efficiency cannot be improved." Liu Yuan said. "We can only work on the category of lottery tickets, by increasing gross profit margin to offset logistics costs." When Xu Zhiming initially designed Kuai Shubao, he considered diversified directions, "the gross profit margin of books is very low, and the market environment is very transparent, only doing books, there is not much room for survival." When Liu Yuan introduced the A round of financing, he had already planned to expand the range of categories, using snacks just as a tool to attract customers, "in the sales data of large supermarkets, food sales can account for 60%, but the profit contribution rate is only 15%, this is enough to explain the problem. Plus, we are all agency products, it's hard to really get enough gross profit from upstream." The question comes again, what kind of category is most suitable for short-distance B2C? "From the customer demand perspective, it is necessary to prioritize categories with strong instant needs; from the product attribute perspective, it is necessary to prioritize categories with high standardization degree, not high packaging requirements, relatively small volume; from the participant perspective, it is necessary to prioritize categories with relatively high order value and gross profit; from the policy regulation perspective, try to consider areas not restricted by policies." Qian Hao said, "relatively attractive categories also face their own challenges." "The first two attributes of food and daily necessities are better, but there is a trade-off between gross profit margin and transportation costs. If the quantity of a single product purchased is more, then the transportation cost will greatly increase. The first two attributes of drugs and tobacco are also good, but limited by legal regulations, it is difficult to roll out on a large scale." And under the current user base, Xu Zhiming does not need to think so complex yet, "I select products around the daily needs of office white-collar workers, then try them one by one. After all, books are the main product, and other categories only account for 20% of total sales." In the case where the logistics issue cannot be relieved, this method is obviously difficult to expand quickly, and the long tail effect still needs time to realize.