It's not to say they don't have torque wrenches but they're usually a lower cost click type and not always used. The reality is that most torque wrenches (and their users) are not super accurate - so if I spec something at 6nm I need to ensure it's still functional at 5nm and doesn't break at 10nm+.
Bicycles suffer from an interesting conundrum where people don't believe they should cost a lot and they don't believe the labor should be expensive. That pressure / expectation means that many shops don't operate at a super high level and many mechanics really aren't getting a ton of training. There are really top tier shops that do a great job, but they are charging $150+ an hour which many cyclists simply won't pay for. But there is no way to attract and keep talented mechanics and spend the time to do things the right way for less.
Almost every part on a bicycle is not only safety critical but is also a single point of failure. Which is something I try to keep in mind when we design and test new products. There is a lot of proprietary gear in the bike industry that makes it really difficult for mechanics (and owners). Obviously we do a lot of design on the computer and then at the factory - but I still check and assemble things in my own shop to make sure they work as we intended. That's all to say, it's a bit different than what a bike shop is doing.
just like a teacher…
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