This is fairly typical. Though I'm in marketing and advertising, I subcontract the design work and act as a liaison between the two. Even with a clear discussion upfront (goals, action steps, rough schedule, etc.) this situation is impossible to avoid. Many companies do their marketing/advertising/branding by committee, which is a huge mistake. Typically when I'm going through fifteen or more revisions, that's the cause.
When that happens, I try to have a frank conversation with them about the costs they're racking up and the time they're losing by trying to please everyone on the committee.
When that happens, I try to have a frank conversation with them about the costs they're racking up and the time they're losing by trying to please everyone on the committee.