Most recipes have some slack in them. If you're dialing in a single shot of espresso, you want to make sure you have an exact weight for inputs and outputs. If you're baking a cake, 7 grams difference in how much flour you use doesn't matter.
Notably, for a lot of ingredients, recipes don't even try. "4 eggs" is always approximate since eggs aren't the same size. Recipes with peppers always mention you need to play around and use judgement because both size and capsaicin amounts vary quite a bit from batch to batch.
Yup. I see a lot of "cooking for engineers" engage in this sort of false precision. In truth, for a huge number of recipes, you can dramatically vary ingredient amounts with no major consequences. And even in baking people overstate the needed precision. Even if you weigh flour in grams, your eggs are imprecise and your mixing technique is imprecise and your oven temperature is imprecise and the times listed are imprecise (have you ever seen a recipe say "bake for 22 minutes and 15 seconds").
Notably, for a lot of ingredients, recipes don't even try. "4 eggs" is always approximate since eggs aren't the same size. Recipes with peppers always mention you need to play around and use judgement because both size and capsaicin amounts vary quite a bit from batch to batch.