An for another view entirely:
For the moment, lets leave "troubleshooting" out of the argument.
Let's say that the person can follow directions, can take things apart and put them back together again with no parts leftover, has the proper tools, Knows how to re-work a board, The things that get fixed must pass certain tests as suggested from the "simulator".
So, we don't necessarily have shoddy work.
What we have, I don't know. The "group" could be dysfunctional.
i.e. The tech going to the manager and saying, I spent too much time on this, can you assign someone else. This "someone else" does the troubleshooting, possibly alone for a while and then "teaches" the lower tech what he did and why. The "lower tech" could then complete the repair and test.
I had a conversation with friends and workmates that at times "A little bit of my time can be be worth a lot of yours".
Two real stories:
Two PHD electrical engineers spent an entire weekend trying to figure out why a test fixture sparked. I solved it in 5 minutes the following day.
A bad ground in an electrical outlet.
A friend (self-employed in the industry) gave up as to why an aspect of a design he did for himself didn't work. I had the design info and even a blank PCB. He concluded that the chips were defective and got replacement chips. He then described to me a valid test. I had an AH HA moment and checked the logic levels on the datasheet. For some of the inputs to the chips, the logic was TTL compatible, for the CHIP SELECTS it was CMOS. So, a level shift and a firmware change fixed it. I'm in the US and he is in Australia. It's possible that I might build it, but it does use some obsolete chips.
One manager of mine, I think knew this and he knew it was good for the unit. My requirement, was to report things I did that would take longer than 15 min to a half hour.
This does become a problem and did when you, yourself have a huge project to do and are supervising someone else at the same time.
The other one counted beans and that appeared the extent of it. He's like "Don't help anybody" unless you get permission, yet people still came to me. He could count the important beans electronically and complained that when other people did "as aspect" of my job, he counted more beans. The job had aspects that were uncountable and my quality of work was probably too high.