The number one reason people buy a product, or a service is recommendation from peers. When I have a great experience with a service provider, I tell everyone I know. This is not different in B2B marketing and selling.
The fastest path to deal closure is a strong set of peer references - customer to customer engagement.
Unfortunately, getting B2B marketers and sellers to relax and let their customers talk to each other is not always easy. In a desire to control the message, the discussions can move into stiff one-sided monologues that do not yield results. Results that turn into advocacy for the brand.
Advice to marketers and sellers: if you have an opportunity to let your customers talk to each other in a Customer Advisory Board or other setting, take it. Let your clients do the selling and marketing. You will get the best ROI of your career and you will learn a lot along the way.