unfortunately this does not hold up to reality, in many cases building the right stuff from the beginning is either too long, and you will be late to the market, or simply impossible since you don't have enough information from customers using the product.

Among the many wrong reasons to the Agile way of working being able to change and adapt to reality is a valid and important one.

I don't know which army are you referring to, but my army reverted to heavy bombing if smooth haven't worked.