Having the authority to sanction a president does not necessarily mean that person has the power to overthrow a president. And the people with the most direct power (military and secret service) lack the authority to use it. Mostly these factors can balance out so that power is not concentrated as much as it seems.
IIRC Atatürks' turkish constitution demanded that the military overthrows the government if it devolves into tyranny.
It's literally how Stalin got in power.
Ever heard of voting?
You’re downvoted because it appears cynical about something that appears to have no reasonable alternative but you’re correct