I've just read a HBR blog describing a customer profile that salespeople need to avoid: the "Talker". Talkers are people whom, despite being a friend of yours (or your product); despite strong connections with purchasing decision makers; despite repeated assurances of assistance, somehow fail to close the deal for you.
This passage, in particular, struck a chord:
There is a troubling paradox in the Talker. This profile embodies much of what sales leaders tell salespeople to seek out in the ideal stakeholder: they are accessible, they provide great information, they act as a hub for networking, they are pro-supplier — the list goes on and on.
In the end, however, these very traits ultimately harm their credibility inside the organization. The access they grant to the supplier and their energetic backing of that supplier results in doubt amongst their peers. Indeed, our data show that Talkers are anywhere from four to six times less able to build consensus for a purchase compared to Mobilizers.
This reminded me of the KM (knowledge management)/content management/Intranet projects I've been involved in before. For some reason, there was always at least one "Talker" leading the project.