Ideally it is not a matter of one or the other making better decisions but making different decisions.
In a well functioning democracy, elected officials and career civil servants have two very different jobs. Elected officials synthasize public opinion in order to establish public policies that reflect the will of the majority while respecting the rights of the minority. Career civil servants operate programs to implement those policies effectively and efficiently. The system begins to break down if the elected officials become so deeply involved in implementation that relatively uninformed public opinion forces out technical expertise in program operation. The system can also break down if career civil servants begin to use their control of program operations to advocate for or against public policy positions. Each group needs the other, Each should make an effort to understand the other. Practioners in one area should be able to tranistion to the other and add value in both areas. Each should avoid trying to do the others job.