But by economic necessity you probably had to give up on such people after x weeks of training, right?Time will not equal success in a trade.
As a welder for the good part of 20 years I have worked with many willing /enthusiastic people who will never get the hang of it.ever.
Who is to say that after 2 years they might not be very competent? After 10 years they might be excellent?
But business necessity probably means you won't hold on to them past their probation period if they aren't showing good progress from the beginning.
Not everybody learns at the same rate, but I don't believe for one second the slow learners can't master welding, eventually.