Unit replenishment during campaigns

[Zumwalt_446]

When transitioning to a new campaign scenario (at least in the early stages of the campaign), a large portion of fallen out/destroyed units are typically returned to duty or replaced. This occurs over a duration of (typically) only a few hours until the next scenario's start time.

Are the replenishment rates/quantities typically seen reflective of real-world metrics, or are there some "gameified" components of this mechanic that diverge from real-world? No criticism if this is the case, but I'm curious what the philosophy was/is for this area of the game design.