Various methods are available for analysing needs. Reliable statements can be expected if customers are involved in the needs analysis. A customer survey can be used. However, it is better to actively involve lead customers in the development process. Looking at competitor activities can also provide insights. Also look at companies that are indirect competitors.
Example: A company produces pipes made of polyethylene. In order to identify market and demand developments, it is worth taking a look at manufacturers of pipes made of other plastics, e.g. polypropylene, but it may also be worth taking a look at steel pipe manufacturers.
Often, only a look at customer benefits directs attention to ideas for innovations. You can ensure relevant market information via an ongoing corporate foresight process.