You don't wash cast iron pans. There are a few reasons for this.
The most important reason is that food cooked in a cast iron pan adds character to it. It starts to shape the flavor of what you will cook in the pan later on.
What is remarkable about this, is that no matter what you cook, the pan seems to improve. When you cook the perfect batch of maple bacon, the pan gets better. When you turn chicken thighs into charcoal briquettes, the pan gets better. This seems to defy all logic. Seems to.
You see, in many ways, programmers are cast iron pans. We learn in much the same way. We just need to adjust our psyche to recognize it. Everything we create, from the masterfully architected permission system to the detestable hack that brought down production adds to our character. Our seasoning.
It is important to remember this. Too often a terrible experience can frighten us, and make us weary about approaching a similar problem in the future. It is time we cast these fears aside. Don't think of errors, or victories as battle scars and awards. They are valuable experiences. They are your character. Your seasoning.
In many ways, mistakes teach us more than victories. We know what to watch out for the next time, but we need to give ourselves a "next time" for this to work.
So fearlessly make your mistakes. Fix them. Grow from them.
Because if you manage to grow a little everyday, you're going to be huge.