A tradesman spends more time as an apprentice than obama has in federal government. I sure as heck wouldn’t want someone with 143 days experience building my house.
Similarly, you would want the pilot of an airliner to know what all those little "thingies" do; and also you might want your heart surgeon to have a good decade experience.
Also, you might want your Commander-in-chief to know the difference between, say, a Chief Master Sergent, a Chief Petty Officer, and a Chief Warrant Officer, (and also between Navy and Marine lieutenants and captains.)
You might even want the President to know how many states comprise the United States, but perhaps that's asking too much.