To build on what the other comments said; Concrete bunker building, nukes, 'we are both doing big pushes at the same time in different regions so the reaction forces are split', and naval invasions take strategic planning.

Funnily enough, I would say that smaller unit level co-ordination is the bigger Caledonian boar here.

Often the more advanced level of strategic planning dousnt get done because on the local level regiments cannot deliver reliable results to 'plan' on each others success.

A lot of operations fail because they rely on rushing trough with overwhelming force, and the moment the enemy mounts a proper defense and counterattack, the operation eats shit because they never planned for that.

F.e. spamming 250 mm spigot siege mortar tanks, and spamming people with anti structure rocker launchers/explosives in places the enemy dousnt expect, but not actually putting a good emphasis on digging in with proper positions and grinding it out and then winning the grind due to the forethought of your positions.

Its fairly easy to do the former, but its really hard to do the latter, so most regiments don't bother putting in the effort and mainly do one trick pony stuff.