[whateveracct]

It's a desire to be lazy ;)

The gist is - by having many simple-but-powerful tools along with many simple-but-powerful ways of composing such tools, it makes programming real problems way less intense. The cost of course is the learning curve. So I think of it has shifting variable cost of development to fixed costs upfront.

The end result in my experience is being able to handle more complexity than otherwise (good for side-projects.) Or to handle the same complexity with less time and effort (good for FT engineering...to make room for said side-projects.)

(Those terms actually have very general and simple definitions that I've seen interns learn in one teaching session. But they are infinitely useful problem solving techniques that I use all the time.)