Why did Zhao Can Li Chun work in Han Dong for 30 years? Isn't the term of office five years at most?

Zhao Lichun, of course, did not work as a provincial party secretary for 30 years, but worked in Han Donggan for 30 years. It is estimated that officials from all over the Eastern Han Dynasty worked as officials and then rose to the provincial and ministerial levels. I remember in the original novel, Zhao Lichun worked in Han Dong for nine years. It is estimated that 30 years, that is, starting from the grassroots, then slowly going to the county bureau (or possibly transferring), and finally staying in the deputy provincial and provincial posts for about 10 years, a total of ***30 years, this is still normal. Therefore, Zhao Lichun is starting from the grassroots level and the Zhao family is taking root.