Comment by citizenpaul

IME it often comes down to "big men" issues where someone important wants the data in a certain way that is not logical or consistent so they won't let the "tech people" simple take the data and present it in a way that is logically consistent and follows best practices. They want to sit in meetings and create their own mental model monstrosity and force the devs to make it. Once that happens one time there is zero chance of the company ever having a consistent data model at any point in the future ever.

Not really a problem that can be overcome in probably 99% of companies. Lots of consultancy money to be made for the sake of ego and inflexibility though.