Earlier quoted context omitted.
> Turkey's GDP peaked at $950 billion in 2013, just before Erdogan became president. By 2017, it had slid to $850 billion Do you realise that Erdogan has been in power since 2001? So if economic downturn is his achievement, then the economic growth is his achievement, too.
He had significant checks and balances when he was the prime minister. Many of them are removed, nearly half of the executive powers lie upon the president, without any balance, currently. This is thanks to "presidential order"s ( Cumhurbaşkanı Kararı ), which is separate from "presidential decree"s ( Cumhurbaşkanlığı Kararnamesi ), which can be struck by the constitutional court.
That I know, too. And that happened (as in many authoritarian states) so that he could maintain the illusion of legitimacy: "hey look, I'm not a prime-minister forever, I am now president".
But do give Erdogan some credit. He is not stupid. And it's disingenuous and deeply simplistic to paint what happened in Turkey as "Erdogan became President in 2013, look Turkey immediately slid into recession because of that". "Checks and balances" alone cannot explain Turkey's growth prior to 2013.