[em-bee]

you can't compare the US here. a prime minister is not just like a speaker of the house. in many countries world wide the prime minister takes on most of the responsibilities that in the US are fulfilled by the president. the prime minister effectively runs the country, while the president is just a figure head having mostly ceremonial duties. the role of the president in the US is different, and an exception to the common rule.

at least some of the reasons why the US president has a term limit could therefore also apply to other countries prime ministers.

[3vidence]

The US president has way way way more power than the Prime Minister.

The prime minister is more or less a privileged PM.

He is not the head of the military, cannot create executive orders or anything of the like.

[em-bee]

that is true, but in the countries with a prime minister i know about, as far as i am aware, noone has that kind of power. in other countries the concept of an executive order appears not to even exist. in my brief search i only found something comparable in france can be issued by the council of ministers. everywhere else only parliament can do that. nevertheless in those countries the prime minister is the most powerful person running the country, and the president is a figurehead.