Nc6 blocks in your c pawn. C5 is a typical pawn break that is central to many black defenses when playing Against d4 openings. On top of that, there are some plans where your knight is better suited on d7 anyway. If you want to play an early Nc6, you can look at the Chigorin defense (there are a few openings named after him).
So I have been playing chess for a decent amount of my life and I have never gotten why the comp says that e6 is better than Kc6. It seems like e6 blocks light square bishop movement and stops you from activating a knight, right?
Please help me understand this.
Thanks