Iteration with continuous integration. They've been developing this game series since before 2000. There's absolutely no reason to keep tearing the whole game down, developing all the components separately, and then trying to glue it all back together in crunch time. When they started work on Rome 2 they already had Shogun 2 complete and in perfect condition! Just fork Shogun 2 and iterate!

Replacing the incompetent managers with better ones.

It's all about incentives. The leadership has incentives to generate as much profit as possible in the shortest possible term.

Ignore existing and generate new technical debt? Yeah, this will cause problems years from now...

Drive death marches, promise them things you won't deliver, shit on employees. Sure, they will burn-out after the completion of the project, by that time my bonus check has arrived.