"Starting Over" In Your 30's

A recent discussion on Quora led me to write this response to a question about what it's like to change careers in one's 30's.

If you have found your passion, and can transition to the new field by repurposing some of the basic skills in your old field in some way, you will be in a great position to move forward.  That is, it feels like a fresh start, looks like one on paper, but also isn't quite like you are starting from zero, since you have already developed some life skills that you'll be surprised to find apply in your new field in a wide variety of unexpected ways.

Here's my personal example I shared on Quora:

Although my graduate degree was in Sociology, my first professional jobs were in software development.  It was much easier to get a job as a coder, Q/A-er or marketing person in software than as a Sociologist, even with an advanced degree -- even though I didn't study CS and had just picked up some of those skills along the way, in the early 90s, as the public internet began to become "a thing".
But over time, I was drawn more and more back to my roots, in personal and organizational and cultural areas.  And in my early thirties, I used my tech background to start writing self service HR apps and then do HR ERP implementations.  I then gradually moved into a HR role that involves no day-to-day IT skills.  I'm focused on cultural issues, leadership coaching, organization design, and change management.
Did I really "start over" in a new field?  Yes, but I leveraged my old field, which helped give me a leg up.  How?  I do this HR work for large software companies, and I'm one of the few HR people that has sat where my clients, the coders, and even our customers, people buying enterprise software, sit.  So "starting over" actually gave me some advantages -- because of what I learned before I "started over".

In short, it's pretty cool to start over in a new field because you are not really starting over.  Even if it's just having learned how to function in the workplace, you have a big leg up over people that are truly just starting out.  And you also have the confidence from your varied background to know more about what you like and what the other paths are, out there, and that you have chosen what you want to do, not just what you have fallen in to.