I left tech some time ago for medicine after being a SWE for 8 years (currently in Medical School, but I initially considered Nursing School too).

Burn out played a role, but the most driving factor was that I couldn't care about what I was working on most of the time. I didn't want to spend my productive years adding the next useless feature, "making that button pop", or tweaking the sign up form to try to increase sales. I felt that I wasn't using my time right.

I saved enough and quit my job. I could've made a lot more money if I kept working as a SWE, but now the feeling I have that I'm doing the right thing for me is well worth it. So far I'm very happy with the change.