For ease of reference:
- armies which cannot attack any more: "stuck armies"
- armies which can still perform an attack: "mobile armies"
It's really very simple: stuck armies are the first to get killed; only when a territory runs out of those will mobile armies start to die.
To the best of my knowledge there's no way to actually see
how many armies are "stuck" or "mobile"; WL only shows the total amount.
One thing to keep in mind, attack-only or transfer-only orders which didn't take place do
turn the armies they would've applied to into stuck armies. Let's say you have:
- 10 armies on a territory
- first order: a transfer-only order for 5 armies (to a territory you lost before the order takes place, so the order is skipped)
Now, if you give a second order, the following happens:
- a maximum of 4 armies are available: 10 armies in total, minus 1 defender which has to stay behind, and minus the 5 armies which never actually did anything, but still count as being stuck
- if "attack by percentage" is enabled, an order to "50%" of your armies will result in 2 armies following that order.