[mrandish]

I'm not sure shyness is a problem. Some of the most effective and big dollar-earning enterprise salespeople I ever met were quiet introverts. They were successful because they took the time to listen, understand customer's problems and genuinely try to help. They also had deep product and domain knowledge.

[muzani]

I second this. All the top salesmen I knew, even the charismatic ones, were really introverts.

Part of their charm was practice, part of it was excitement for the product, part of it was some kind of inner fanaticism to help the customer.