Lets have a little situation here. Lets say a zerg and terran are playing standard vs each other.
Situation 1 zerg kills 30 of terrans 50 workers while hes on 3 base, the terran is basically dead unless the zerg is stupid.
Situation 2 terran kills 30 of zergs 50 workers while hes on 3 base, 1 cycle of drones would be around 18 drones, so he only needs 2 production cycles to remake those drones.
The larva mechanic is what makes zerg so forgiving, if a terran gets fungled badly then the zerg can go over to their base and kill them more often than not, if the zerg loses his army he has a much more likely remax potential.
You where the one saying how easy larva inject is, so zerg should have plenty of larva to remake drones, or overlords, or army units for any mistakes they make.
I would say the larvae is the greatest gift and curse. It centralizes all production. That means you only need to hit ONE timing for your production on one base, when you miss it however it is the worst because it affects so many aspects of the game.
Say you had to land a MULE down to activate half of your production buildings. Well, really if you can hit your mules, ez peazy. However, there is no way to play a game hitting it dead on every time and it will have larger repercussions because of that.
I have seen many terrans prolong their games with MULES to make up the difference long enough to kill a zerg, or protoss for that matter.
Terran is the most unforgiving with their army however. They have no delay mechanic like a force field, they have nothing that can be made in a panic like warp ins or the speed of remax from a zerg (closest I can think is repair, but it doesn't come close to that effectiveness).
You have the army or you don't, it is a very black and white game for a terran (as far as I can tell). Having extra resources is by far the worst thing as terran, because there is no way to "quickly" add them to your army either.