Kano model
The preceding example illustrates a common survey instrument, which is used to ascertain the relative importance of one requirement versus another using a scale of five to nine points from the lowest degree to the highest. This tool is also often used in conjunction with a rank order scale, which asks customers to rank each requirement from 1-N so the company can identify the highest-ranking requirements.
The problem with this methodology is two fold. In many circumstances, the customers will say virtually every requirement is important or very important to them. There is no downside to ranking virtually everything as important or very important.
The other problem with this tool is there is no way to know which and how many requirements absolutely have to be in the product. Nor is there any way to know which requirements will be competitive differentiators and will delight the customer, resulting in them buying your product rather than the competition's.
These questions can be difficult...
