There are a lot of good candidates from the Electoral College to the make-up of the senate to lifetime appointments on the supreme court, and on and on ... I've felt (since 9/11, to be more exact) that where this system fails so massively is the way it locks an administration in office for 4 years with no way to change course: The president gets elected every 4 years and short of high crimes and misdemeanors, there is no legal way to change horses. So when a president is elected because he's not tainted by the presidency of Bill Clinton (or Joe Biden) and we end up attacking Iraq, or Venezuela or Greenland, there is nothing that can be done to correct course. We're stuck.
A couple of things happen because we're stuck. First the decisions made by the WH become the new reality and politicians everywhere, including the Congress (first and foremost) immediately resign themselves to embrace the new status quo because they don't have the authority to change direction. And the presidents know this. So the second thing that happens is that presidents can get brazen and can push things as far down the line as they feel comfortable. So if Nixon does not make the boneheaded decision to break the law, he would've continued to execute the Vietnam war despite popular protests even though he claimed he had a secret plan to stop it. No immediate consequences mean no consequences in politics.
The third thing that happens is that it bolsters the perception that nothing we, the voters, do really matters. They can lie to us, or the situation changes and with it, our priorities, and there is not a goddamn thing anyone can do anything about it. How does that help the sense of nihilism, which has already been in the water for so long for a whole bunch of other reasons.
The lack of a strong feedback system for the executive and fear of an instant collapse in support has consequences. It is anti-democratic in crucial ways.
There was one idea advanced by Ezra Klein (this was before abundance) which was to make impeachment a more regular thing. Which ... is not that simple. You still need something to prosecute, and bad policy is not a thing that's easy to prosecute as a high crime or misdemeanor. Also, impeachment is about changing the person in charge and very often it would not force a policy change.
So what's the solution? There is none. We don't have the equivalent of vote of confidence or snap elections. You can't have that under the presidential system, which separates the executive from the legislature (plus the congress itself is a mess when you have only two parties and partisanship is on the rise). I'm bringing this up because at some point, hopefully not too far in the future, we will need to build a second republic because this one is pretty much done. We will need to scrap everything we currently have (that means the existing constitution, and put together something better and more rational, more workable. When that time comes, this is one of the knobs we need to pay extra attention: make sure that governments don't fall willy nilly, but when something big happens and enough people feel that "this was not what we voted for", we have a course of corrective action we can take that does not require some underlying crime or misdemeanor on part of the top of the executive chain. We should not have to wait for 3 more years when the person we put in office turns out to be a psychotic 12 year old throwing a constant tantrum that brings the whole house down.
And yes: we need to start thinking about the second republic and what will replace the ruins of a 250 year old worthy but failed experiment we're living in right now. Ideas need to be on the table and discussions need to happen before talking about stuff like this are made illegal.