In my late twenties, I received an offer to work for a small consulting firm. After six months in, they asked if I would be willing to travel overseas for assignments. Although I love traveling and would have loved to say "Yes", I didn't because I was blinded by maintaining other work simultaneously in the country in order to gain more money.
Six more months pass and I receive an email from my director stating that they needed to have a meeting with me as soon as possible. However, when I joined the call, human resources is on the line as well. Long story short, I was laid off due to lack of work to provide me. I was upset at first but had another job waiting for me. Fast forward a year later, the company gets sold and everyone working on my team are all promoted and received salary increases. That could have been me too.
Over time, I realized that the opportunity to travel overseas was given to me so that I could get acquainted with the company taking over the firm I was employed with. Since I chose not to travel overseas, I shot myself in the foot by forfeiting a future opportunity which would have catapulted my career at that time.
When opportunities are missed, the worst thing you could do is start speaking the ‘Should've, Could've, Would've’ lines of thoughts. Instead, take the 'L' and learn from it so that you won't miss any other opportunities in the future.