This angle is strange to me. A salesman doesn't exist as an island. He's selling products or services from a particular company, no? And if he leaves, he would

This angle is strange to me. A salesman doesn't exist as an island. He's selling products or services from a particular company, no? And if he leaves, he would then be selling products or services from a different company. Yes, maybe some clients will like the salesman enough to switch suppliers, but surely the fact that it's a different company with at least somewhat different products/services matters too, no?