John Wyndham asked “Why was I condemned to live in a democracy where every fool's vote is equal to a sensible man's?”
In the Platonic tradition everyone should stick to what they are good at and most people are no good at statecraft. The same may well be true for any specialist subject. If you were about to undergo brain surgery would you be inclined to rely on a brain surgeon or take a vote amongst all the patients in the hospital? Would you rather your airliner was flown by a pilot or elect someone from amongst the passengers?
If you agree that specialist tasks should be performed by specialists and yet consider yourself a democrat then perhaps you are either a person who believes that running the country requires no expertise, or else someone who conflates the idea of the most popular with the idea of the best.
Yet the alternative is even less attractive. Of late a whole class of politicians who know no trade but politics has grown up. These professional politicians are not in the service of democracy.
It cannot be democracy where most constituencies are safe seats for a particular party and where the choice of representative is effectively restricted to the person approved by a small number of that party's activists. In practice we have even less of a democratic choice in politics than we do in electricity supply. The sooner we move to open primaries the better.
Moreover, although we have travelled a long road from the days when the leading citizens of each borough used to select two of their number to travel to the capital for short assemblies, decide basic issues of taxation and supply and thereafter return and explain matters to their fellow citizens, I see no good reason why we should not require any prospective MP to live in a constituency for at least two years before being eligible to represent it.