It can have many answers. Usually It is said when someone means that there is no place of emotions in business. The statement in question can mean: When doing business, relations(especially family relations) should not come between. In business only those relations are kept which are profitable and when relations become unprofitable, then they should be eliminated, doesn't matters how deep they were. This rule of business is usually applicable in corporate environment. It is even now practiced that for business' profits we can harm others OR enjoy on other's expense. It is like defining the old saying-Everything is fair in Business wars instead of Everything is fair in love and war. Corporations usually spy on their competitors and love to harm them thus, complying with this new self-made rule by them.