In "Dead Men's Path," why do the mission authorities choose Michael Obi as headmaster?

In “Dead Men’s Path,” Michael Obi is described as being the type of “young and energetic” person that the Mission authorities want to send to Ndume Central School. The school was “unprogressive,” meaning that its students were less successful than those at other schools, so the authorities wanted a headmaster who would work hard to improve it. Obi is very well qualified. He had completed secondary school and earned the designation of “pivotal teacher.” He was only 26 years old when he was chosen, and he was better educated than many of the older headmasters. Michael is enthusiastic about his progress to date and about the possibilities that the new position presents. His vision of the modernizing mission he will undertake is compatible with the Mission authorities’ goals.