A good YouTube tutorial would tighten bolts circularly and how the resulting deformation. This is my point: if the failure mode is illustrated in a way understandable by a layperson, it seems totally reasonable to trust the youtube tutorial over a contractor. After all, the contractor is looking to make money, just like the YouTuber.
> the contractor is looking to make money, just like the YouTuber
That's a very valid point. The question is who has more skin in the game. Contractors have more of a positive feedback: if I am satisfied, I will recommend them to my friends and relatives. YouTubers may have more of negative feedback (not that much since dislike button is gone), but it takes someone to call their bullshit and write a refuting comment. I don't think lots of core YouTube userbase is inclined to do so, the default behavior there is to make a "pffff" and swipe away.
