Presidents who rule African countries in their 70s

The retirement age in Uganda, East Africa, is 55! The lady who told me happens to be from that country and it hit me rather hard when I realized that the president of that country Yoweri Musevani, is 75 years old and has refused to step down. In fact the news from the country says that he is contemplating live presidency! The continent of Africa is very sick, I challenge anyone to convince me otherwise. Why would Ugandans allow a 75 year old man dominate them? He has been president for close to 37 years and right now he is not willing to step aside. What a continent! Zimbabweans just got rid of Robert Mugabe who has been in that position of president since the Southern Africa country gained independence in 1981!
Do these old men think that there is wisdom in not wanting to leave office for other people to run the business of governance? The age of presidents is a reoccurring decimal in many African countries: Nigeria and Ghana are other examples. Both presidents are in their 70s. Many of the youth in these countries feel that they are being smothered out of active participation in politics. Nigeria recently announced a constitutional amendment that would change the course of multiple political parties and restrict the number of registered parties to what the national assembly say are manageable numbers.  Every politicians should know when he has over stayed his welcome and should be able to quit the scene. But not Museveni. He believes he is real ma coy!