Ask five people in your company what "active customer" means, and you'll probably get five different answers. Sales might count anyone who signed a contract. Marketing might mean someone who opened an email last month. Finance might have its own definition tied to billing cycles.
To be precise, none of these are incorrect. However, the data isn't the issue when a corporate executive downloads a report anticipating one number and receives three contradictory figures from three teams. The language is the problem.