The simplest durable lesson here is this: small recurring costs matter because compounding also works against you. Three quick checks before you act: 1. Name the mechanism in plain English: Investors usually notice big drawdowns quickly. Fee drag is quieter, but it compounds for much longer. 2. Say why it matters for behavior or portfolio decisions: That is why cost discipline is not cosmetic. It is part of return discipline. 3. Set the review question: On the next review, write down the one variable that would make you change your mind. In real life: A strategy that beats by a little before fees can become mediocre after years of friction. Common slip: The mistake is comparing products only on recent return and ignoring what must be paid every year to keep them. The point is not to memorize the label. The point is to know what variable is actually doing the work.