Also pins have to be taken into consideration.
Here the Black Queen is pinned, the White Queen also. Though the Rook on B2 seems to be defended twice and assailed no oftener than twice, it is lost. White simply captures it with Bishop, since neither King nor Queen can recapture. Black must answer K-B1, White continues with B-K7ch., forces KxB and wins the Queen. All this complication arises because the squares adjacent to the spot KB2, also the spot KX1, where the Black King stands, enter into the turmoil.