We elect competitors and complain they seek more power

Our elections are a big competition. Pitiless ones.
There is only one winner and the other go to hell.
And we participate in it. We give our vote to the greatest leader.
It’s exactly like "The Voice".
A competition where only the one prefered by the majority wins?

To get to the presidential election, politicians spend ten years competing, building their success, being greater than others, inspiring confidence to raising money.

And then we complain. 
We complain that our politicians only care about their re-election, getting more power and eliminating enemies.
They are competition beasts.
The greatest among the greatest.
They are made to win, get more power, be the best.

If we want other leaders, we need to change the rules.
No need to criticize them