A little metacognition is a dangerous thing.
And
Better to never begin, than to start and not finish.
There are many very painful pubescent phases of development, including in metacognition, self awareness, theory of mind and emotional maturity.
Narcissists are stuck at a hellish level of development, having just begun to form a self, but not enough to stabilise it. They admire psychopaths (as with the case of Trump to Putin) because the psychopath never even started a process of developing a proper self/other understanding, secondary emotions and empathy. So psychopaths appear so much more regulated and unaffected by the world - however incapable of relating in omni win ways. The narcissist wishes they could be like that... but they began. And only just began at that. Like having grown little 6 year old legs but being expected to run with 20 years olds - of course they will cheat to keep up.
Narcissists are emotional infants - terribly dependent. But even most adults are only emotional teenagers (hence the phrase 'life is high school')
Better to never begin, than to start and not finish. But best of all is to make it through and mature, because something new can come into form and stabilise and that thing is love.