Combat minimum damage rules

[ElDonReal]

I generally like combat in Civ5. It is often predictable, so you can plan your actions very well, but a few battles just turn out different and give some variation. However, I don't like the minimum damage rule a lot. In each combat the attacker seems to lose at least 1 HP. In each ranged combat the attacker seems to hit at least 1 HP.

What is the reason that every unit has to inflict/bear at least 1 HP in every combat?

For example, I often choose the ranged defense promotion. But I feel it doesn't help a lot as I'm still often experience that 1 HP was deducted before and 1 HP is dedcuted afterwards.

[Boracks]

I've often had older ranged units do nothing against more modern units. Close to the same era, yes, damage always seems to occur. But I've had archer shoot at rifle and miss.

[gdijedi7]

Really?

They hit my B-17s all the time.

And when I bomb Brutes, it's funny on one hand and sad on the other. You should see their torches fly all the way to 15,000 feet.

Which is stupid.

[ElDonReal]

Yes I have seen units doing no damage, but that was some versions ago. Especially Archer vs City didn't always do damage. Recently however, I seem to always getting some damage from ranged combat and I also always seem to lose at least 1 hp regardless of which unit attacks which.