I was fired from a job where the boss had it in for me. He was a really experienced dev, but he was also very arrogant. He hated me questioning him. I didn't have the evidence nor the "political" clout to back up my criticisms.

It was humbling.

I realised two things:

keeping your mouth shut is often the best approach.

And

my own arrogance was keeping me from getting better, from learning new things. Not just for the company, but for myself.

I want to write better code, make better design decisions, utilise design patterns, actually think about what I'm doing, and be able to justify why I'm doing it.

I want to be able to choose the best tools for the job, not the best tools for me.

I want to be a person that is open to criticisms and I want to be someone who is always ready to learn new things.