Salesforce did it recently. It's about division of labor. https://fortune.com/2018/08/07/salesforce-keith-block-co-ceo...
“I am going to be focusing on, No. 1, the products, the technology—as well as the culture,” says Benioff, “and Keith is very much focused on the operations and distribution functions of the company. We feel it’s going to naturally align with both of our strengths.”
Product, Marketing, Vision, Culture -- vs -- Sales, Support, Services (Business)
It basically reverts back to what start-ups would segment out as Business v. Technical co-founders.