About a year before I retired I thought I would work for about 3 more years. This was late 2017, just before my 59th birthday and I figured I'd go to 62. During 2018, I was just getting more and more frustrated.
+ I was in an IT sales engineering role and the industry was changing yet again (more reliance on cloud, hardware getting harder to sell, more of the interesting work was being done on the software side (where I wasn't)).
+ My company had gone through a merger and as much as there was a goal to have the entire combined company act as a unified organization, it wasn't happening. There was still a lot of in-fighting and distrust. There were incentives in-place driving different parts of the company, who were supposed to be aligned, to go in different, conflicting directions.
+ Management was be coming even more numbers driven than usual. The final straw for me was at a mid-year review. Despite all the frustration, I had had quite a good half-year - beating my goals by a healthy margin. Rather than any positive feedback, management lit into me (and almost everyone else in my position) for not doing even better. (It didn't help that my own management was being goaled and evaluated on metrics other than my peers and I were).
Shortly after that review, I scheduled a meeting with a financial advisor that I had been working with for a year or so, and asked him to validate my thinking that I was in a position where I could leave. He assured me that I could. I was going to do it towards the end of the year - but was so unhappy, that I decided to pull the trigger in early September. My boss asked me to stay on through the end of the August-October quarter, which I agreed to do.
My last day was November 2, 2018.
So, I guess you could say it was fairly abrupt vs. my original and even against my revised plan - but looking back, best decision ever!!!!
Retired in November 2018 at age 59. No regrets.