You're right that it is good to have every method "do one thing".
The art of programming is dividing up a huge messy process into a series of actions that each are understandable as "one thing".
When you look at code that successfully does this, it seems easy and obvious. Those who are good at it sometimes think of it as easy and obvious in the way that mathematicians call some hard problems "trivial".
But in general, making everything do just one thing is hard and an art-form. But still good to do.
The art of programming is dividing up a huge messy process into a series of actions that each are understandable as "one thing".
When you look at code that successfully does this, it seems easy and obvious. Those who are good at it sometimes think of it as easy and obvious in the way that mathematicians call some hard problems "trivial".
But in general, making everything do just one thing is hard and an art-form. But still good to do.