The most common pour-over mistake isn't grind size or water temp—it's pouring like you're putting out a fire. You swirl the kettle, dump in half the water, and hope for the best. The result? Channeling, where water carves paths through the coffee bed and leaves the rest dry. That's why you get a cup that's both sour and bitter at the same time.

I've seen this with home brewers using perfectly good beans. They blame the roaster, then the grinder, then the kettle. But the habit is the problem. You're not pouring—you're dumping.