There are so many issues involved with letting someone else do something for you (finding/chosing the person, trust, explaining what you have to do, moving the person to the place, schedule/calendar issues, negotiating the price, legal issues, …) that for many things, it’s less efficient to pay someone to do it than to do it yourself
There would be vastly more things like this if specialization wasn’t normal. That’s what I meant when I said that it works better the more it’s done. There are things it’s better to do yourself, but most things aren’t like that.
And finally, you’ve to consider emergency situations.
The benefits from a situation not covered by the rule I gave earlier are very small. If you’re in a situation where acting would be remotely dangerous, don’t. If acting would be perfectly safe, go ahead. If it would be very slightly dangerous, then you’re likely to be better off doing a Fermi calculation.
There would be vastly more things like this if specialization wasn’t normal. That’s what I meant when I said that it works better the more it’s done. There are things it’s better to do yourself, but most things aren’t like that.
The benefits from a situation not covered by the rule I gave earlier are very small. If you’re in a situation where acting would be remotely dangerous, don’t. If acting would be perfectly safe, go ahead. If it would be very slightly dangerous, then you’re likely to be better off doing a Fermi calculation.