Why, just why are the sieges way weaker than ambushes?
An ambush is capable of defeating a whole 6 armed dwarves caravan + a 5 Steel armoured army, putting the whole fort into a state of "let's all go mad together, possibly killing each others".
3 months later, a two squads ambush comes, nobody wants to pull the lever that closes the main bridge. The whole fort is now being protected by a short corridor, 3 wide, with two rows of cages and only two weapon traps, only with a few crappy weapons in them.
The two squad leaders manage to get captured and their whole army just stay near the cages. Fortunately for them a tantruming dwarf comes their way, and some comes after him, begining the wipe out of the whole population, that tries to resist with the few weapons and armours I have for them.
The battle let 5 dwarves in the hospital, a baby and a child in the main room, and a massive amount of animals, including a horse that the only remaining invader have been following for 5 months now, not managing to do real damages, and runing in circles around the fort.
Soon, the baby and the "injured" (two only had light injuries and would have been perfectly fine working) starve and dehydrate to death.
In the mean time, the child drink the reserve of booze and eat food, in quantities sufficient to last two years at least, and the chickens reproduce so much that there are many of them everywhere in the fort, like they were the inhabitants.
Why can't I have a fort wiped out at least once when it doesn't involves me actively doing it? (flood, magma...)