If the seller is selling only himself, then he just stops working for someone else and open up its mediation office. Why would he wear portfolios from employer to employer and lose some customers during the transition, if he can once and for all do their customers only, and selling its expertise and knowledge of the market – where the customer is better to be serviced in the next year or the next purchase. If we still have examples of people who move from employer to employer with its portfolio of clients, it is not known at all, anyone who hires him, and from someone who depends. In such cases, most likely, the seller itself, gets in the face of the employer required him to share such office. If we are talking about a top manager with the team, then all is even worse. What do you think is the reputation of the manager at a previous job? And that feels the employer when such a manager as well, with the team, go to your competitors? Moreover, in such a "team" is often not fully professional line – svoyachestvo.
People often go to their leader because they do not represent themselves and are afraid of getting fired if they will go back. How much should be diffident a top manager to be afraid to leave his team? Why do He must not have enough strength and skill to hire a professional again? Was it because the last time he did not hire, and took a job "its" and these "its" is simply no more? And do not you think that such a Manager-in-command just scared prospects new leadership team? A true leader is never one with itself does not drag. He respects people and gives them a better choice. Took root in the new job, he can talk to his former subordinates, and, again, in terms of their interests and needs, rather than their desires.