This is not an "origins" question like this one: What are the origins of the words 'zwischenzug' and 'zugzwang'?
I know enough German to know that the term means "in between move." Another translation I've seen is an "interpolative" move. My question is why make such a move?
An example is when a rook wants to go to the seventh rank. So it first goes to the eighth rank, let's say with check, and when the opponent replies, the rook goes back to the seventh.
What might be the advantage of using such a "roundabout" route to get to the seventh rank.
In GO (where I'm higher rated than in chess), it might be called a forcing move. You make a "throwaway" move that forces a particular response, and then you make your main move, and the two together are stronger than making the main move alone. How might this work in chess?