We all know the drill….you build comfortably through the seven-days-protection period and start gaining might in making troops. But sooner or later, the upkeep in food they need will outnumber what you could possibly produce in your city. Especially for armies over 200k might it is nigh impossible to keep up with the needs, even with a high level hero helping production and wilds to give you bonuses.
Constantly asking alliance members is annoying and impossible, as they will also grow their respective armies. Luckily, there is a caveat in the KoM system to help you out.