I do not know what you mean by "use a wrench correctly". I mean, I do not see how a person can use a wrench incorrectly.
Can you hint at what I am missing?
ADDED. There is a widespread standard for which way to turn to loosen a bolt and which way to turn to tighten it. Maybe that is what you refer to.
ADDED. If you use the wrong size wrench (i.e., slightly too big) you can "strip" the bolt (i.e., turn the hexagon into a circle, thereby making it impossible to wrench the bolt in the future even with a correctly-sized wrench). And as Romeo mentioned, not everyone is born knowing that the longer the lever, the easier it is for a person to apply a given amount of torque. And you can apply too much torque, thereby stripping the threads, which can lead to failure of the bolt to perform its primary function (holding 2 pieces together) and can make it impossible even to replace the bolt with a fresh bolt. On the other hand, if you do not apply enough torque, the bolt can shake loose. And speaking of shaking loose, you can forget to put in a lock washer where it is needed (with the result that the bolt shakes loose). So yeah, there are things to learn.
Gee, after I put myself in the right frame of mind, I can think of plenty of ways to use a wrench incorrectly. I withdraw the question. I would add however that people should not wait to receive training for using a wrench because it one of those things that can mostly be learned by experience (the purpose of lock washers being an exception to the general rule).
EDITED my first sentence to make it less likely to be interpreted as a potential put-down.
Removing and installing mechanical fasteners (bolts and screws) is more complex than you might assume. It goes far beyond selecting the right size tool, and turning it in the correct direction.
A mechanic develops these skills gradually over decades- a master mechanic would often have no trouble removing a corroded bolt that a novice mechanic would destroy for example. Conversely, they can also install a bolt in a manner with less chance of failure down the line.
Some (but by no means all) of the issues involved include:
So, transferable skills: skills that, upon improvement, increase your ability in other areas (and also improve other, higher-level skills).
A basic example would be reading/writing. Knowing how to read and write allows one to access a huge amount of other skills and resources which are otherwise unavailable. A less obvious example would be clear speech (enunciation). Ability to speak clearly improves one's prospects in a lot of different areas (e.g. professional advancement, dating, etc.).
I'm looking for additional examples. Which skills did you find to be most transferable? Did you become proficient in X, and then found this helped you in many other areas of your life? Please share.
(I tried to find whether this was discussed before, and failed; if it was, I would appreciate the link.)