This is a vastly underappreciated aspect of government, and of human social institutions in general. The principles-on-paper version of something can be mediocre, or just plain horrid. But if the actual people running things are sufficiently capable and caring, the on-paper failings doesn't much matter.
Flip-side, even a perfect-on-paper system, implemented with incompetent & uncaring people in charge, will be crap at best.