There are hundreds, if not thousands, of reasons not to do anything. After a very successful twenty year career in business, and equally successful thirty-seven years practicing business, property and environmental defense law, I say Go FOR IT. The number one reason of my past success has been curiosity coupled with the ability to take risks and do what no one else had thought of or done. Along the way, or more accurately, ways, I failed innumerable times, but learned a lot, and built on both successes and failures.
As far as the established disciplineis concerned, well known Stanford professor Robert Sapolsky has opined that everyone should change their career, as it is the new person to the discipline that approaches it from a novel perspective. Thomas Kuhn, dealing with Scientific Revolutions, would suggest the same. My own view is a little different. As long as you are learning more and more about life, you are engaged in a course of conduct that is fairly limited to human beings, even if it only enhances your personal knowledge and worldview. From the standpoint of physics you will be processing more and more information, which could be asserted to be "negative entropy."
From a practical standpoint, now working on my Master's degree and a third bachelors degree, you might want to consider just taking one online course per term from any public and accredited University, which will give you unlimited access to immense resources and database, all at no charge.
Good luck and best wishes!