There are two different definitions of the word tolerance.
In high school, this kid I didn't know brought in an engine block to bore out the cylinders in the metal shop. This process increases the diameter of the cylinder, which can result in increased compression and horsepower. Unless you do it on the metal shop's drill press.
A combustion engine works because the cylinders, where the gas burns, have extremely small tolerances. A professional machinist who bores a block will use a specialized tool that may remove as little as one ten-thousandth of an inch.
If the distance is off by more than a few hundredths of an inch, the engine won't run. Tolerance means the boundaries outside of which the system can't function.
My buddy who told me about this kid was a punk, and got a scornful kick out of it. I didn't say anything; but I didn't feel scorn either. Life sucks without growth, and growth requires not knowing what you're doing for a while. Balancing between growth and safety requires hella discerning judgment.
Discerning judgment doesn't depend on education. Take the Harvard grad I talked to a party one time, who did major damage to his car's electrical system while trying to install a stereo amplifier. I quote: "I figured, guys with GEDs do this, how hard can it be?" Ironically, he had to take his car to "those guys" to get fixed. But he rationalized his ego: "If I did this for a living, I'd learn it faster than they did."
If you work with with your hands, you understand this in your everyday life. But lately I hear a lot of people talking about things they don't understand. Healthcare, climate science, politics. Do you hate elitists talking down to you? That's understandable, but you need to make damn sure you're not suggesting the equivalent of putting an engine block on a emetal shop drill press.
Tolerance means the boundaries outside of which a system won't function. In order to be successful at anything, you need to make some system function, so you need to know those boundaries.
Expand your tolerance.