(;C[Black plays.

Source:
    "Good and Bad Style"
    Go World #8, p. 41]SZ[19]AW[qa][rb][rc][qd][pd][re][oe][ne][ng][pg]AB[qb][qc][rd][oc][nd][me][ld][mf][jc]

(;B[pa]C[Poor judgement.];W[pc]C[White can simply push.  Black will have to take a big loss.]
(;B[pb];W[ob];B[ra];W[oa]C[A disaster for Black.])
(;B[ra]C[No better.];W[ob]))
(;B[pb]C[Bad timing.  The kyu player knows that this point is part of the correct shape, but may not recognize that the move order is crucial.];W[oa]C[An unexpected shot that exposes the weakness in Black's incomplete shape.];B[pa]C[Black cannot cut here.];W[ob];B[pc];W[nc]C[Black has a liberty shortage.];B[ra];W[od])
(;B[oa]C[The correct shape that shuts out White.  A kyu player can calculate that this move is correct, but a dan player just knows that this move is correct.];W[pb]C[White can try this hane, but ...];B[pc]C[... Black calmly blocks.];W[ob]C[Pushing doesn't work.];B[nb]C[Now White is the one with a liberty shortage.]))