You usually don’t convert the units in the day to day. Either something is a few inches, a few feet, or a mile away. Construction workers can usually measure stuff out by hand (literally) if they’re doing stuff like framing.
A cup is quite literally a standard cup size. Any modern recipe will just be like “2 ¼ cups of milk” you can measure it or eyeball it. Anything smaller and you’re using measuring spoons anyway, so conversion doesn’t matter again.
You usually don’t convert the units in the day to day. Either something is a few inches, a few feet, or a mile away. Construction workers can usually measure stuff out by hand (literally) if they’re doing stuff like framing.
A cup is quite literally a standard cup size. Any modern recipe will just be like “2 ¼ cups of milk” you can measure it or eyeball it. Anything smaller and you’re using measuring spoons anyway, so conversion doesn’t matter again.