Some of the problem is the candidates.  Some of the problem is the bureaucracy that is so big and uncontrollable that if you elected the most perfect candidates for every electable position, the bureaucracy would still make it nearly impossible to change most of the problems without removing >99% of the government agencies/employees. 

 The bureaucrats will make sure that nobody wanting to eliminate the bureaucrats can ever be elected or even get traction. 

 Job security through election manipulation