They end up choosing a role that they don't want because they're scared of doing the role they do want, or because someone else tells them that they would be good at the other role.
I advise people to choose deliberately. Choose a role that you'll feel successful and happy and proud to say you do, and that will teach you skills you want. Do a job you’re excited by. You will learn to get good at it by doing it. I feel like we don't admit it often enough enough that most of the time, we won't do a job well on day one. The vast majority of our learning happens on the job.
There's another consideration though, especially when people make this decision in college or when they're junior. Taking a step away from a more technical role closes doors. It's not fair, but our industry biases are set up so that you really need to have a solid engineering resume before you take a non-engineering role.