The first conscious decision I've made in my entire professional life is to leave academia, where in retrospect I remained more out of inertia than as a result of conscious decision.
When this first conscious professional decision started to have practical implications, I thought I would have to unlearn everything I had learned in my academic life, which spans almost two decades since I received a "driver's license" for "academic highways" and about three decades since I started teaching in the university, first as a PhD student.
But to my pleasant surprise, the more progress I make in my study of a new career and its neighboring areas, none of which has anything to do with academia, the more clearly I realize that my decades-long academic life has left me some legacies I can reuse and have already started reusing in my new professional life path.
What I consider the most important legacy of my academic life is the skill to study new things from scratch. Since I was a child, I've always been fond of and good at finding new sources of knowledge from the minimal existing sources of knowledge. Actually, I had no choice but to develop this skill as I was born and brought up in a very remote place with no one to ask for advice and recommendations.
Though I find myself now blessed with some amazing teachers and mentors for my new professional life path, this skill comes in handy, and I also enjoy finding and digging "gold mines" by myself. The most brilliant one I've found and started digging on sabbatical this academic year is (Chabad) Hasidism, especially the Book of Tanya, and its profound teachings.