I believe the sentiment is that the Miami Heat are only so good of a basketball team (namely, theoretically not as good of a basketball team as the Pistons are), and so, if the Pistons play at the top of their game, can only do so much/win so many games in this series. That's "necessary" and unavoidable. When the Pistons play below that point, beyond anything directly forced by Miami, they unnecessarily make things a lot more difficult on themselves.