Imagine I gave you three ingredients to make spaghetti. I gave you the pasta, the marinara sauce, and cheese to top it with. The only catch was that you could only use each ingredient in certain amounts. What if I said you could have either 0, 500 grams, or 1,000 grams of each, but nothing in-between? Well, certainly, you’ll need pasta if you’re going to eat spaghetti, so let’s say you chose 500 grams. Unless you’re a marinara fanatic, twice as much sauce as pasta is going to be way too much. Even 500 grams to match the spaghetti is excessive, but then again, the only other option is no sauce at all. And what about the cheese? That’s going to be a lot of cheese.
The problem, of course, is that it’s not just how much of each ingredient is present that matters, but how much is present relative to the others. What if I gave you finer gradations, say steps of 100 grams each? You could probably make a pretty good approximation of your preferred meal, say 500 grams of pasta, 200 grams of sauce, and 100 grams of cheese. If I gave you 50 gram gradations, you could get even closer. For the record, the ideal meal is 473 grams of pasta, 167 grams of marinara sauce, and 56 grams of cheese.