Why would Shakespeare have Duncan and his guards killed offstage?

There are several reasons as to why Shakespeare chose not to depict Duncan and his chamberlain's murders. Shakespeare wanted to convey that the murders were too terrible to portray which is one reason he chose not to show the audience. The audience is also in awe of how characters can enter Duncan's chamber and walk out a changed person. By the power of suggestion, the brutality of the murders are amplified. Previous to the murders, the audience is unsure if Macbeth will follow through with the assassination. By not depicting the murders, the audience is also left in suspense. The audience only finds out that Macbeth committed regicide after he tells his wife. Shakespeare also wanted his audience to feel some sympathy for Macbeth throughout the play. By choosing not to depict Duncan and his chamberlain's murders, the audience does not view Macbeth as a monster, but rather a helpless pawn caught up in the Weird Sister's web of fate.