Rather simple. If you answer 1 e4 with ...e5, then 2 Qh5 question mark (attacking the e5 pawn, but developing the queen too early) 2...Nc6, guarding the e5 pawn and developing a correct piece, then 3 Bc4 (threatening checkmate again), now Black defends with 3...g6 (gaining a square for the black bishop on f8 and a tempo against the prematurely moved white queen). Then White plays 4 Qf3 (threatening f7 again) safeguarding his queen, then Black plays 4...Nf6, developing yet again, blocking the checkmate by a process called "interposing" and preparing to fianchetto the bishop to g7. White no longer has an opening advantage, and now needs to be thinking about simply equalizing(!)
Notice that this knight is protected by the queen on d8! Now finally, White can INSTANTLY lose the game if he tries to attack again with the move g2-g4 question mark, trying to win a piece by attacking the pinned knight on f6. . Black counters this by playing the very powerful counter-attacking move 5...Nd4! , attacking the queen on f3 and threatening to win a rook on a1 with a fork on the unprotected pawn on c2!
THIS is why you don't move your queen out too early! Bad things happen if you move your queen out too early when it can be exposed to attack and enemy development at the same time (there are some cases in chess where you can move the queen early, this is usually to pressure a pawn or assist in a pin, but in these cases, the queen can't be attacked, so it's serving a useful function). But we're not done yet!
White now decides to guard his hanging, unprotected pawn on c2 with 6 Qd1. The THIRD MOVE by the queen in SIX moves--and the queen is BACK ON ITS ORIGINAL SQUARE! Now Black gets an almost winning position by attacking the center and white's exposed pawns and pieces by the move 6...d5! A *triple* attack that has a very powerful tactic behind it. The g4 pawn is attacked, the e4 pawn is attacked and the bishop on c4 is attacked! White responds with 7 exd5, removing the attacker on the Bc4, but Black responds by not taking the pawn on d5, but playing Bxg4, attacking white's pathetic Queen again! White must play 8 Be2 with a massive disadvantage, but if he tries to play f3 to attack the black bishop, the f3 pawn is actually pinned, so now Black plays the unexpected 7...Ne4!, which opens up his own queen to attack white's severely weakened kingside. Threatening 8... Qh4 check followed by mate, and white can't take the bishop because he still gets checkmated on the f2 square, and taking the knight loses the queen on d1.
Against the Sicilian Defense, 2 Qh5? is even worse, because after 2...e6 (guarding c5), there is no 3 Bc4, but if White decides to "attack" with 3 e5? (stopping the ...Nf6 gain of tempo on the Qh5), e5? is a VERY poor move, Black plays 3...Nc6, putting pressure on e5, and threatening to play 4...g6, attacking the white queen, and preparing 5...Bg7 after that. The "natural" move 4 Nf3 simply blocks the queen's retreat: 4...g6 force 5 Qh3 Bg7, and the white queen is very misplaced and the e5 pawn is in serious danger of being lost. Black is already winning.
I hope this example helps put 2 Qh5 into the garbage bin where it belongs.
How do you respond to White....
Pawn to e2, Queen to h5, Bishop to c4 ?
Always seems to throw me off.
Thanks in advance.