From the perspective of the narrative, the wargaming table is a micro snapshot of the battle raging all around.
The contact point in time that you have command over.
But, in terms of the table, how can we use it from a tactical perspective?
In most wargaming rulesets you are not allowed to leave the table with your units, as that would represent leaving the battle. There might be an occasion special rule or forced circumstance, maybe even a unit with a special rule, but this is not the majority of the ruleset.
Can we use the table to shut down the movement of our opponent?
The fact that there are physical boundaries to exploit?
This is why controlling the center of the table is an important primary tactics regardless of the mission.
Block of the center of the table with some units, project that attack radius out from them, and two things happen.
If it is a physical ground game your opponent can't move past the unit mass in the center without removing them- burning game turns and resources/dice to do that. Layer some long range units behind this center mass and you have that many game turns of free use.
If it is a more fluid game- with space or sea ships which can move past, setting up a blockade means they have to go through you- again taking losses and spending game turns.
What units do you have in your system and army list that can project some dice through shooting or attacking, yet are cheap and numerous- as this center mass will be and is expendable. We want them to be able to inflict damage, but the physical positioning and blocking becomes more important.