I'm genuinely curious - why are you disappointed?
Putting my nose in where it's not wanted ... democracy may be the worst system invented but better than anything anyone else has got, but it can be seriously undermined by the dishonesty and lack of integrity of its elected representatives. Opens the door to even less savoury and extremist characters who would 'clean things up' but be tyrants in the process.
Anyone across the political spectrum who is competent and effective in government is usually something the public welcomes. Those who think outside of the box, who say what they really think rather than parrot the accepted script. You know where you are with them. Pain in the neck to the establishment. Such characters are often popular amongst those who otherwise would not support the party they belong to. Hence the disappointment when they let the side down and make you wonder if there is anybody left in politics who is there for the good of others and not prestige and/or financial benefits. Serving self whilst pretending to serve others.