It's like translating grandma's units of measurements from her old recipes.
"A smidge of this, three sprinkles of that, and a can full of something that does not come in a can" (The can was her 'measuring can' that was some kind of weird size that doesn't exist anymore)
Edit: After she passed, we threw the can away because we didn't realize it was the can and load-bearing to most of her recipes. After some best guesses + trial and error, we concluded the can was approximately 7 ounces / just under a cup.
When they said "7 ounces / just under a cup." that's not a particular physical cup. A "cup" is an exact measure in the US, it's 8 fluid ounces, which is 236.5882365 milliliters precisely.
Even if the US does go metric, it will take a lot longer than 50 years for people to not know how big a cup is, all measuring tools in every kitchen are marked for them and the other common units like tablespoons and teaspoons*, and virtually every recipe uses them.
Well, that's how I usually do my estimations on software projects.
If I'd go through the work to make an exact estimation, most of the work would already be done - and then I still wouldn't be 100% sure, that the approach works, until it's tested
So, I kinda eyeball what I'll need to analyse the problem, create a concept, implement and test it - and leave some spare room for getting back to step 1.
Honestly this is less true the more you bake. I find myself tearing recipes apart and substituting/modifying amounts of all sorts of ingredients.
Sure if you want to make a fluffy white cake or a classic chocolate chip cookie you better do that by the book but you can get pretty creative with baking if you know what you're doing.
This is me with cooking. My chef will regularly ask me how much of each ingredient I used in a particular dish I created and every time I'm just like "dude I just kept throwing shit in until it tasted right"
Don't get me wrong if you give me a recipe I'll follow it to the letter, but if I'm making something on the fly there's not a single thought about measurements.