Why do leaders only use people they recruit?

On the one hand, most leaders attach great importance to employee loyalty. As long as you are loyal to him, he is willing to train you even if you are weak. Because a loyal sheep is easier to control than a centrifugal lion. That is why many executives leave with their own people, because these people are the most loyal to him. On the other hand, leaders are more cautious than employees. The higher the position, the more cautious the leader is. Don't dare to use it for people you don't know. Because it costs you to train a person, you must first understand the advantages and disadvantages of this person, and then arrange a suitable job for him. It takes time and cost. What if the hard-trained soldiers finally resign? Therefore, leaders will not easily believe that they did not bring it out by themselves. Between employees and leaders, it often takes some time to get along well. Moreover, the employee's personality does not match the leader, and the leader will also consider it. So many leaders don't like to use new people because they are useless. According to this unspoken rule, if you want to work across departments, you must think clearly whether the department leaders are willing to accept you. You should learn to judge whether the leader accepts you superficially or sincerely. If you don't change jobs, you'd better not change departments. I met colleagues who changed departments, and none of them succeeded in staying.