One key reason for the introduction of category management was the retailers' desire for suppliers to add value to their (i.e. the retailer's) business rather than just the supplier's own. For example, in a category containing brands A and B, the situation could arise such that every time brand A promoted its products, the sales of brand B would go down by the amount that brand A would increase, resulting in no net gain for the retailer. The introduction of category management imposed the condition that all actions undertaken, such as new promotions, new products, re-vamped planogram, introduction of point of sale advertising etc. were beneficial to the retailer and the shopper in the store. A second reason was the realization that only a finite amount of profit could be milked from price negotiations and that there was more profit to be made in increasing the total level of sales. A third reason was that the collaboration with the supplier meant that supplier's expertise about the market could be drawn upon, and also that a considerable amount of workload in developing the category could be delegated to the supplier. The Nielsen definition of a 'category', used as the basic definition across the industry, is that the products should meet a similar consumer need, or that the products should be inter-related or substitutable. The Nielsen definition also includes a provision that products placed together in the same category should be logistically manageable in store (for example there may be issues in having room-temperature and chilled products together in the same category even though the initial two conditions are met). However, this definition does not explain how the process often works in practical retailing situations, where demographic or marketing considerations take precedence. The next step of Category Management is to understand the mechanism of the customer's decision concerning purchases of a given category. The decision-making process is usually analysed by observing customers directly in the store and by direct surveying. The result is recorded in the Customer Decision Tree (CDT)  The industry standard model for category management in retail is the 8-step process, or 8-step cycle developed by the Partnering Group. The eight steps are shown in the adjacent diagram; they are :  The 8-step process, whilst being very comprehensive and thorough has been criticized for being rather too unwieldy and time-consuming in today's fast-moving sales environment; in one survey only 9% of supplier companies stated they used the full 8-step process. The current industry trend is for supplier companies to use the standard process as a basis to develop their own more streamlined processes, tailored to their own particular products   Market research company Nielsen has a similar process based on only 5 steps : reviewing the category, targeting consumers, planning merchandising, implementing strategy, evaluating results.