And in my experience it takes two, if you're good at what you do. You probably get more responsibility for systems that deeply affect people's lives and the world around us as a new grad at Facebook than as a mechanical engineer, which is probably part of it. And you probably do pick up more skills about building reliable systems, threat modeling, product planning, etc., all of which would be transferrable to other types of engineering. It's unfair that people working on a global CDN can see the results of their work in seconds and people working on a military weapons contract see the results of their work in years, but it's true.