Good Account Managers know the business inside and out, because mostly, they have worked most or all of it from the ground up.  Some good Account Managers didn’t work from the ground up, but were curious enough to go visit those departments, ask questions, (sometimes to the point of being annoying) and learned how things work.  Good Account Managers are CEO of their accounts and assigned customers. They act like business owners and they measure their success by the success of their customer’s experience.