How often have you found yourself working on the requirements for a new feature and got into a heated debate about what your users actually want or need?
If only we could conduct some user research. But we don’t have the [time, budget, resources] to conduct research, so we’ll just skip it.
But these debates are understandable (especially if you skipped the user research). Departments within an organization have relationships with different types of customers -- and, even if they do have a relationship with the same customer, their interactions with them are different.