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As opposed to normal monsters, even in 4e. You can do some rough calculations and figure the 60hp Ogre can survive for X number of rounds against the villagers. If they have a 60% chance of hitting the Ogre, and do 5 points of damage each, that is an effective damage of 3 per round, so they would defeat the Ogre in 20 rounds. Conversely, the Ogre will hit the villagers 80% of the time and do 5 points of damage, for an effective damage per round of 4pts. Villagers have 5hp each, so unless the Ogre can split an attack between two villagers, that would be 16 villagers before he is defeated. If the evil wizard that is behind all this is casting spells also, then you can calculate the damage based on their percentages of being able to save to get the effective damage for the spells.
Unless the villagers are minions, in which case, the numbers start getting wonky. Miss effects are canceled, so the wizard is instantly less effective against the minions than they would be against villagers with hit points. The minions are more threatening than regular peasants because of that.
Theoretical exercise, you may be thinking? What if the PCs have to defend this village? Sure, you can just pull a number out of a hat for the number of villagers that are killed. But you will have no idea how long the PCs have until the villagers are all killed or the enemies are driven off. Arbitrarily picking a number of rounds is the same as tripping a flag in a video game; ie, it has nothing to do with the PCs actions other than clearing a stage or surviving for a certain number of minutes.
Which is fine, if a given group likes that kind of thing. But it demonstrates that minions are problematic for building a world, and that these 'weaker' opponents are more dangerous than regular monsters, depending on who you are. A serious problem when trying to simulate an independent world.