Symptom: The (internal) Sales (client liaison) function exists but is not well trained and is not added sufficient value.
Internal selling (client liaison) is not simply a matter of taking clients to lunch and telling them what they want to hear. The (internal) Sales (client liaison) function must add value by helping clients think through their business strategies and identifying high-payoff opportunities for the organization's products.
Every (internal) Sales (client liaison) professional in the organization should trained in a proven method of strategic analysis; the method allows them to talk to high-level clients, find find the highest payoff, strategic use of the organization's products, and explain their logic afterwards.
An explicit method for opportunity identification (problem finding, not problem solving) is necessary for a number of reasons. It will improve the effectiveness of even the best (internal) Sales (client liaison) professionals. It is the basis for training new Sales staff. A logical process ensures that the recommendations can be explained afterwards. And by documenting a method, the method can be improved over time as the organization gains experience (a process of organizational learning).
On the other hand, if the method of opportunity identification is left to the intuition of (internal) Sales (client liaison) staff, results will be difficult to defend, payoff will be inconsistent, and the process may be impossible to replicate.
(Internal) Sales (client liaison) professionals also add value by helping clients justify their investments in the organization's products, and facilitating the client responsibilities during the implementation of the product. Additionally, they may help clients band together in consortia that share purchases, coordinate a client that is making a number of simultaneous and related purchases, and facilitate communications between clients and the rest of the organization.
If the (internal) Sales (client liaison) function is not adding enough value (e.g., doing no more than "glad-handing"), they may lack training in the methods of their profession.