In order for a client to become a buyer (at least, a buyer for anything significant), he or she must feel a sense of urgency around a problem that needs to be solved or an opportunity that must be capitalized on. Without these fundamental conditions, no-one will buy.
One line of questioning that may be helpful could explore performance gaps. Someone who does sales training might ask, "How many of your salespeople will miss their quota this year?" or "How many of your salespeople are currently able to support your new product/services strategy?" You can ask about current performance versus plan; about the expectations of senior management in areas of customer service, revenue growth, cost containment, and so on; you can ask about business potential versus current achievement–for example, "Your XYZ business is currently around $50 million…what do you think the potential is for you? What’s getting in the way of capturing that potential?"; and so on.
A second strategy is to focus on personal aspirations, needs, and goals. Where does this person want to go in their career? What’s their next step? What criteria or metrics is management using to evaluate their performance this year? What is frustrating them about their current business performance?
Finally, you might bring a strong point of view about the industry that is designed to shake people up. This might address changes in competition, technology, regulation, etc. that are about to have a profound effect on your prospect’s operations.