Sending the same message to everyone is shooting yourself in the foot
If you send the same message to your entire database, you are wasting opportunities. A CEO of a 500-employee company does not have the same needs as a freelancer. Segmentation is what separates campaigns that convert from those that go to spam.
According to McKinsey, companies that personalize communications based on well-defined segments generate 40% more revenue. The foundation is having quality data to segment.