If you made a mistake, you learn by not making the mistake again. It also helps to read about mistakes made by others so that you don't make those mistakes either.
Depending on what company you work for, there is a reasonable amount of money to be made as a mechanic. You can learn to be a mechanic at a school like ITT Tech.
its so you can focus on your game and not be distracted by the mistake. also so you can learn from that mistake like what to do and what not to do.
To not make a mistake twice
Simply because - assuming you remember what you did to make that mistake - you'll avoid repeating the mistake in the future.
Keep being her friend and learn from her mistake.
There is no reason. You just make them. you just make mistakes and you learn from them when you make a mistake you mostly didn't know what to do or what to write.
To become a bike mechanic, you can start by taking a course or apprenticeship at a bike shop. You can also learn through online tutorials, books, and hands-on practice. Gaining experience and knowledge about bike maintenance and repair will help you become a skilled bike mechanic.
Acknowledge the mistake, learn from it, and forgive yourself. Focus on the present and the steps you can take to prevent a similar mistake in the future. Practice self-compassion and remind yourself that everyone makes mistakes.
You can learn what is a good diesel mechanic school at web site http://www.mechanicschools.com/ and http://www.indeed.com/forum/job/diesel-mechanic/schools-US-good-schools-Diesel-Mechanic-training/t144829.
Bounce back and learn
The education background of a diesel mechanic is a lot of schooling. One will have to learn air brakes, cooling systems, diesel motors, and power trains to become a diesel mechanic.
If you make a mistake, most of the times you know not to do it again, but some people do not learn by what they have done wrong and continue that way.