Why the Senate should punish and reward Governors

I think the former governor of Kiambu County, Ferdinand Waititu was the first elected official to be impeached in Kenyan history. He did not resign or fall sick; he was removed from office by the Senate. Waititu was impeached due to the pending corruption charges and claims of his abuse of office.

Seeing how Waititu was dishonorably running out of the office and humiliated on the media, that situation got me thinking. What if a governor is good and not bad? What would happen to him? Will he be rewarded for his good performance, or does the system only punish those who do badly? I mean what if another governor used his office well and was never linked to any corruption cases, would the Senate reward him/her?