Although product sales are affected by factors such as market competition, customer demand, and seasonal changes, most products will experience a life cycle from growth to decline. From the perspective of traditional manufacturing, in the introduction period, the proportion of new product development costs is still high, and the market performance is average. A large amount of marketing costs need to be invested to attract early customers to try; in the growth period, the product gradually opens up sales, sales increase rapidly, and production costs gradually decrease, which will also attract a large number of competitors; in the mature period, the product is recognized by the market, and the output increases and the cost decreases. In order to avoid homogeneous competition, it is often necessary to increase investment in product quality, specifications, functions, packaging, etc. to gain competitive advantages; in the decline period, better substitutes will appear in the market, and product sales and profits will continue to decline until they eventually exit the market.

It is not difficult to see that by comparing the two dimensions of time and sales, sellers can infer the development trend of products and take appropriate operational measures to obtain maximum benefits. It is worth noting that although most products on the Amazon platform are also affected by the life cycle, the existence of reviews has extended the life cycle of many products. Some links with more than 5,000 reviews can continuously extend their life cycle and maintain a high sales ranking for a long time as long as the quality is stable.

On the Amazon platform, each listing will go through the following four stages from being put on the shelves to becoming a hit listing: introduction period, growth period, maturity period, and decline period.

When a listing is in the introduction period, its ranking value characteristics are low ranking, large fluctuations, and no upward trend in ranking.

The fluctuation line chart of the major category ranking of the listing within one month, the dotted line in the figure is the trend line. It can be seen that the ranking of the listing fluctuates moderately, and its fluctuation range is much smaller than that of the introduction period listing. The overall ranking value rises from 300,000 to less than 50,000. The overall ranking is from low to high, and the ranking trend line is an upward trend. The above phenomena indicate that the listing is now in the growth period.

When a listing is in the mature period, its ranking value characteristics are that the ranking remains high, the fluctuation is low, and the ranking trend is stable.

The fluctuation line chart of the major category ranking of the listing within one month, the dotted line in the figure is the trend line. It can be seen that the ranking of this listing fluctuates slightly, with its value fluctuating slightly between 3,000 and 7,000. The overall ranking performance is excellent, and the ranking trend line remains basically horizontal. The above phenomena indicate that the listing is now in the mature stage. When a listing is in the decline stage, its ranking value characteristics are from high to low, moderate fluctuation, and a downward trend.

A line chart of the ranking fluctuations of a listing in two months. The dotted line in the figure is the trend line. It can be seen that the ranking of this listing fluctuates moderately, with its value fluctuating slightly between 3,000 and 20,000. The overall ranking performance is from high to low, and the ranking trend line is a downward trend. The above phenomena indicate that the listing is now in the decline stage.