You get more out of your time, but many people want that due to pressure to succeed.

A lot of people think stimulants just keep you going longer. They do that, but for a large number of people they greatly improve working memory, problem solving and systematic reasoning.

I know students that take Adderall because their lives are so complicated that they don't have space for regular studying. So they take an Adderall the day before an exam and cram the whole semester in a day. They ace the exam and don't remember much a few weeks later. Similarly I have seen programmers (and been an example) who have a project to deliver but other stuff going on and use Ritalin or Adderall to pull the whole project out of the bag to the expected standards in a tiny fraction of the time it was predicted to take. And others who use the same to just produce much much more than their peers. And then others who just take stimulants because they think they need them but don't actually produce anything worthwhile, or just end up staying awake too much and being much less productive overall because they destroy their circadian rhythm.

I'd definitely say that if you don't feel you need them, don't take them :)