You shouldn’t complain about truisms (is the quoted text even a truism? It doesn’t seem obviously true) that lack proper justification beyond belief when your initial premise was “an elected leader is the most competent person for the job”.

Beyond the obvious differences between campaigning and actually leading effectively, there is the very obvious looming spectre of dictatorship. So many dictatorships in the our modern history have started off with promising leaders affecting real change. That is, until they decide they like power a bit too much and start dismantling the democratic machinery that they used to take power in the first place.

You also assert that term limits are bad because it doesn’t allow time for people to grow into the role and demonstrate expertise in it. To that I say: there are other ways to lead and grow and develop expertise than the most powerful political office in any country.

I mean, we have an obvious and irrefutable real life example of what can happen without term limits. Just look at the US senate, the house and the Supreme Court. All of the political bodies are or have been littered without of touch career politicians who spend all their time ensuring no one else can challenge them, enriching themselves and their top supporters.