The Client doesn##Q##t see the benefit
This is a tricky one because many of them won##Q##t tell you they will just keep denying you. You can however ask questions like “How can (your business) help you achieve your goals with this product etc?” They may say something like “We don##Q##t have it in the Budget” which leaves the door open for you to negotiate. You better, however, be able to show them great value if you get them or they will never come back. Make SURE you can deliver not only what you say you can deliver but ABOVE that.