I'll start- the biggest bullet I ever dodged was when I decided not to go to business school. At the time I was living and teaching English in Shanghai, China, and I had originally moved there because I thought that learning Chinese would look great on my grad school application.
After awhile, however, I realized that the best-case scenario of holding an MBA was that I'd go to work for a big-name company and become a middle manager who wears a suit and commutes to work everyday. That sounded like a slow death to me, so I coasted in a job I disliked for a few more years until a friend told me about coding bootcamps. I applied, was accepted, and attended a bootcamp based in Chicago, and today I'm a senior software engineer who loves the creativity inherent in the craft of coding.
I saved myself $100-200k in grad school tuition and 2 years of sitting through multi-hour lectures that I knew I'd hate, as well as a career trajectory that would have added little if any value to my life or the lives of others.
1. https://sive.rs/bronze