I'm a programmer. Written 4 programming books - all Amazon best sellers. Just happened to also start running a company. After enough growth, bringing in a business partner to focus on non-engineering tasks was an important step. Having been on both sides, I value both as different skills. One is not inherently better than the other, but I've found that a person who is either and respects the other is often successful. A few million dollars later, I'd say I've been right.