I had a chance run in with one of my profs and his TA at a bar. He was the department chair but got roped into teaching an undergrad class that semester. He was basically that guy on the right, and the TA was on his way there. The insights into what life as a physics PhD was really like that I gleaned from that conversation is why I'm not the guy on the right and instead found something easy and high paying with a different major. Sometimes I feel like I might have wasted my natural ability, but I think I'm probably much happier. Also, maybe I'm just not that smart anyway and my absence is absolutely no loss to the field.