It cuts both ways though. Apple has routinely exceeded (i.e. underestimated) their own revenue numbers for the past few quarters. From Apple's perspective alone, that sounds good because it means their stock shoots up and they get good press. But it means that people who hedged based on the expected numbers got hurt. That annoys people trying to make a living trading (whether those people deserve to make a living trading is entirely a different issue).

So the analysts correct, and bake that offset into their estimates. And Apple "missed" based on those estimates. So people who hedged based on the new guesses have to dump the stock, and it drops.

That's just the way investment markets work. Apple can't ride the "unexpectedly good news!" waves without getting hurt by the "oops, not as insanely great as expected" quarters.