Be Indispensable?

Can a person be indispensable in the sense that the person's role is absolutely necessary in achieving certain goals? For a person to be indispensable suggests the person is unique at playing a role that stakeholders do not want that person to be replaced. But would that lead to institutional problems?

Whenever any institution changes its personnel, stakeholders can feel the differences or change of dynamics, for better or worse. A few institutional actors can consistently come up with creative strategies and result-oriented activities that deliver value deriving eg societal impact. Should their roles therefore be solidified or extended?

When I first worked as a junior lawyer meant to assist a senior, he did not allow me to get involved in a complex case. He then abruptly resigned from civil service taking his knowledge and skill of the case with him. He was then briefed to carry on with the unfinished business - but what if he had suddenly died?

Some persons may be truly indispensable - like Plato's Philosopher-kings or benevolent dictators, relentlessly advancing public value. But any systems would eventually break down in highly dynamic environments. Without timely succession training, I believe those dispensable successors in title would have to do even better than those indispensable ones to fix the system!