I worked at the AA maintenance base in Tulsa and retired after thirty years. Although I worked in the power plant and was not an A&P mechanic, over the years I had the pleasure of working around some of the thousands of plane mechanics employed on the base. I even had an ex brother-in-law who was a dock crew chief on one of the 737 lines.
I was always impressed by how seriously they took their jobs and how they were quick to tell anyone that they knew people's live could be at stake. The complexity of the work made experienced and long career hands absolutely necessary. The gravity of the job always weighs heavy on new hires and the help they received can't be measured. The online and classroom training that all receive during the length of their careers is extensive.
In all the many different trades at the base, two jokes were always told and I guarantee they're still being told today: Classroom training taught me how to drink coffee. And they wouldn't fly on AA because they knew the guys who worked on the planes. (The first one is absolutely true. The second was is not, especially after the company started flying to New Zealand!)