It's hard to train many younger folk too. They can't handle constructive criticism. Certain things have to be done a certain way with certain tools and certain parts or it's not correct. Example: UL (underwriters lab) test things and classifieds it as it is at the time of testing. Any variations from that voids the UL rating. One part may look identical to another but that part is made by a specific company with a specific alloy. The same part made by another company does not have the same molecular makeup thus voiding the rating and safety of that part.