Why Kh1 ?

This is a position I came to from the Development drill. The computer is suggesting Kh1. Is this just a "waiting" move or did black's prior move [c6] pose a threat to my king on g1?

Thank you in advance!

White's position looks so great that it's surprising that there is no immediate tactical win.  It looks to me as if Kh1 is just a good prophylactic move that avoids any nasty surprises on the dark diagonal. I guess it will be followed by Nce4 and a shift of pieces to the king side. It's not the only good move, since White has a massive advantage

Very good

Almost any reasonable move by White should be good for White. I don't exactly like Kh1, but Black's position seems to be that of the particles in solids or liquids in chemistry (only slightly mobile).

I would play d6 almost immediately (before doing some quick analysis down the line such as Qb6+) to cramp Black's position heavily. If d6 immediately does not let White have an edge, I would be surprised.

Not only is Kh1 passive prophylaxis - it also prepares Rg1-g4 type Freak attack. And the knight can probably take f7.

But my vote would be Nce4 because if cxd5 there's Nd6+ with a reveal of the DSB. Then d6 is my 2nd vote. But stockfish sees everything and you have to trust it. To what depth did you analyse and what's the criticality (as in, how good are the 2nd and 3rd candidate moves compared to the best move)?

Thank you. That makes sense. 

Makes total sense. The drill instructions stress the importance of attacking when the opponent is behind in development. I think you're absolutely right about the Rg1, g4 attack.  Thank you.

It is not a bad move of course, but I see absolutely no reason to deviate from the simple and lethal 1.d6, and I am sure that any reasonably working chess engine will prefer this to 1.Kh1.

Something like 1.d6 Bxg5 2.fxg5 Nf5 (2...Qb6+ 3.Kh1 does not change anything) 3.Ne4 looks practically forced, and Black won't live for long.

yeah, that potential threat was not something I noticed until reading responses.  You have a high rating, what do you think about zone_chess's additional comment about  Rg1 and then pawn push to g4 to initiate a kingside attack? 

Thank you

Computers...

As others have already started, White has a lot of good moves here.  The reason the computer likes Kh1 is simply to avoid any potential tactical issues later by getting the king off the open diagonal.  Additionally, it puts Black (almost) in a type of zugzwang.  Modern engines have gotten very good at this sort of play (where it will take time to shut down any notion of counterplay when the opponent basically has no good moves).

Thank you

Perhaps the computer evaluated Kh1 preferable to Black's playing Bb6+ (or Bc5+) forcing the move.  Usually moves involving check result in a loss of tempo.  In this case, I don't think that it makes any difference.

You have to remember, computers aren't perfect.  They are programmed by humans.