Why in politics there is no retirement age in politicians?

What is the logic behind 80 year olds running a country that has 500 million youth under the age of 25?
Who knows the majority population well?
These 80 year olds should be retiring, and spending time with their grandkids. Not making a mess out of our country.
Why is there a hypocrisy in the government? They have a retirement age, but politicians can continue till they become 90? If there is one rule, it should apply to everyone.
Why are politicians exempt from this? This is total hypocrisy, and at important jobs like politics, you need smart youth who can understand their age group, and have dynamic, forward thinking ruling. We dont want these old guys who have one leg in the grave, and one leg in parliament.

listen to her : http://youtube.com/watch?v=WlXPtYq5yS8

Why are we putting up with these old guys, who dont understand our generation? We are the majority right?

Well.. have not seen video yet but its true, we need youth in the politics but may be one reason is that no one cares about politics as profession so we see only aged people who happened to be in politics because of circumstances.

from the US. i aggree completltey.
we have been trying for years to at least get 2 - 3 terms then go home and be with your family.
they say airline pilots must retire at 69 but they who decide the rules for pilots don't retire ever.