Every executive in a company at a minimum should have a general understanding of other functions. If the CTO knows what selling looks like, then the CTO can bet

Every executive in a company at a minimum should have a general understanding of other functions. If the CTO knows what selling looks like, then the CTO can better assist the sales team. Likewise, if the sales team understands how software engineering works (at a very high level), they'll generally understand that "getting a very complicated feature RIGHT NOW for one deal" is ... not realistic. etc.