Especially in companies and governmental institutions there may be several people involved in purchasing decisions. But to some extent also in families and even for individual consumers.
Therefore you should consider who you need to convince before a purchase is made.
This tool is part of designing the sales process - including the Channels-part of the business model, but it may also affect your value proposition, positioning and the price and revenue model.
Discuss and research who will be part of the decisions process and how important their role will be:
Discuss how that should influence your product and business model.
Remember that some of the above roles will be played by the same individual.