About 5 years ago, I got a certification that dramatically increased my salary potential. I got a job offer at a different company (where 2 former colleagues worked), and asked my current company to match it. They did. No big deal, I liked the work and the people I was working with, or so I thought.

Three years later, I was laid off, and the technology I got the certification in is largely obsolete, or at least, difficult to break back into without experience in the new stuff. Meanwhile, the other company I got the offer from has not laid anyone off, and has seemingly migrated all their employees to different stacks. To rub salt in that wound, the former colleagues still work there.

Lesson painfully learned: switch jobs when the opportunity presents itself. Not a week goes by where I don't metaphorically kick myself for not doing so.

Nowadays, I work in ewaste recycling.[0] It doesn't pay anywhere near what I was getting, but I figure it's a much better use of my skills than stocking shelves or washing dishes. Instead of dicking around with a laptop all day, I can dick around with a hundred laptops all day.

[0] https://www.ebay.com/str/evolutionecycling

Not telling her I wanted her when she was receptive.

To stay at my second job out of college for nine years from 1999-2008. As bonuses were decreased and with 3% raises, I only grossed $8000 more at the end of year 9 than I made in 2001. I got a large at the time raise in 2000.

By 2008, I was an “expert beginner”. I was still doing VB6 that had been deprecated in 2001 and programming on Windows in C and C++ using COM and DCOM.

It took me until 2014 at 40 years old until I became a competent, competitive “senior” [sic] enterprise dev and even then I was making around 20% less than the local market median.

I never made that mistake again after 2008. I kept my skills sharp and job hopped aggressively after that. I have had 8 jobs since 2008.