I freely admit this is a guess, but: I suspect what was trying to be expressed is that for a mature product, the difference between profit and loss comes from the marginal buyers. If 80% of your break-even sales go to your solid buyers, and 10-30% of your break-even sales go to your marginal buyers, it's critical to court those margin buyers because they are the difference between revenue being 90% of your costs and 110% of your costs.

Again, let me say explicitly I am reading between the lines, but it is the closest sensible concept I know compared to what was said.

People in general often poorly understand the degree of capital expenditures made by companies, and I suspect those of us in the software vision may have an even more skewed vision since we see billion-dollar companies started with a laptop and ~50 square feet of office space, but when you have real capital expenditures required to make your product (even ignoring advertising, etc.), those little single-digit-percent wiggles right around the break-even point can be huge.