A question about piece development As opening principles say, you shouldn't push too many pawns in the opening. Instead, you should concentrate more on piece development. However, I have good example where it worked the other way around. 

[FEN ""]
[Event "?"]
[Site "?"]
[Date "1984"]
[Round "?"]
[White "Emil Joseph Diemer"]
[Black "Tomas Heiling"]
[Result "1-0"]

1.d4 Nf6 2.f3 d6 3.e4 g6 4.g4 Bg7 5.g5 Nfd7 6.f4 c5 7.d5 b5 8.c3 a6 9.h4 Nb6 10.h5 e6 11.h6 Bf8 12.a4 exd5 13.a5 N6d7 14.exd5 Be7 15.c4 f6 16.cxb5 fxg5 17.f5 gxf5 18.Qh5+ Kf8 19.Nf3 Rg8 20.b6 Bb7 21.Nc3 Nf6 22.Nxg5 Nxh5 23.Ne6+ Ke8 24.Nxd8 Ng3 25.Nxb7 Nxh1 26.Bf4 Rg6 27.O-O-O Nf2 28.Re1 Kd7 29.Nb5 Ne4 30.Rxe4 Rg1 31.Re1 Rxf1 32.Rxf1 axb5 33.Rg1 Kc8 34.Nxd6+ Bxd6 35.Bxd6 Nd7 36.Rg8+ Kb7 37.Rg7 Kc8 38.Rxh7 Rxa5 39.b7+ Kxb7 40.Rxd7+ Kc8 41.h7 Ra1+ 42.Kc2 Kxd7 43.h8=Q Kxd6 44.Qd8+ Ke5 45.d6 1-0


Why did Emil win? He didn’t follow opening principles. Instead he did 17 consecutive pawn moves at the beginning.
Several reasons I can see:


In closed positions like you have here, piece development is not as important as in open positions.
To me it seems that black played his King's Indian set up, more or less ignoring what white is playing, which generally is not a good idea.
Black should/could have attacked the center in the beginning more aggressively, thereby gaining space for his piece play. For instance 2. ... d5 would be natural (though likely he would have faced some version of the Blackmar-Diemer gambit). 5.... Nh5 would make any progress for white on the kingside very difficult.
Until around move 16 black played OK and should not be worse. White has gained lots of space, but, if black plays 16... axb5 he does not have any weaknesses, while white's pawns are soon getting weak (a5 and g5 are hanging, ...)
Around move 19, black has a clear advantage and should not have tried to hang on to the extra pawn but instead gone for active play, developing pieces, e.g. 19... Nf6 looks good.
Black might have missed the knight fork on e6 (i.e. might have missed that white is not forced to move the queen after 21...Nf6). Because of this, the whole plan with Bb7, Nf6 loses strength, because it just helps white to develop the knight to c3 (while the bishop on b7 is still not all that great).
28...Kd7 is the final blunder, though admittedly white's Nb5 is not that easy to see


So in summary I'd say: Black played too passively and missed some tactics.