A lot of the subtlety comes in because of the rule that you can never completely obstruct the opponent's path to the goal, but you can try to make it as convoluted as possible. Hence people try to multiply the opponent's options (so that they can be closed off at the last minute) and limit their own options (so that the opponent isn't allowed to block their unique path to the goal).
One of the most underrated games I have seen. I rank it as Hex for me: two awesome games, very little known (at least there's a very good Hex strategy book)
https://en.wikipedia.org/wiki/Quoridor
A lot of the subtlety comes in because of the rule that you can never completely obstruct the opponent's path to the goal, but you can try to make it as convoluted as possible. Hence people try to multiply the opponent's options (so that they can be closed off at the last minute) and limit their own options (so that the opponent isn't allowed to block their unique path to the goal).