Why is Bd6 better than Be7, Bc5 and Bb4? [FEN &quot;r1bqkb1r/p4ppp/2p2n2/3p4/8/2N5/PPP1BPPP/R1BQK2R b KQkq - 1 9&quot;]

Be7 protects knight from getting pinned, Bc5 pins the pawn on f2 after Whites, castles, and Bb4 pins the knight.
Whats logic behind Bd6? (It also can't be a battery in future via Qc7 because of 1... Kh1 2. Bxh2 g3, and the bishop will be trapped.)
Part of the problem with Bc5 is that they can respond with Na4, which threatens the bishop and grabs the tempo.  Be7 isn't great because its range is inhibited by the knight and it impedes the kingside rook's power on the e file after you castle. Bd6 is nice because it is protected by the pawns, the bishop can be retreated to b8 or c7 while still controlling either of the second longest diagonals.  I'm a 1500 rated player, so take that into account.