It’s dangerous to have epiphanies while shaving. But in this case it was unavoidable: My epiphany was about shaving.

For the past few weeks, my bathroom routine has been a little like George Clooney in O Brother, Where Art Thou?, minus the smelly Dapper Dan. I’ve been lathering shave soap with a brush and bowl, and shaving with an old-fashioned single-blade, single-edge, unmedicated safety razor.

Specifically, I’m using the Leaf Thorn—a stylish and well-marketed and self-avowedly “aggressive” single-edge razor whose house blades are so wafer-thin the company imprints them with the words “I am not plastic.” The less aggressive Leaf Single Edge Razor is called the Twig, and it's meant to be more gentle than the Thorn. It’s all very cute.

But what I learned, after weeks of baby-smooth shaves with the Thorn, is that I’ve been doing shaving wrong.

The epiphany was something that seems obvious at first: The best and safest blade is always the sharp one. The best kitchen knife is the one you keep sharp. The same goes for scissors, and for the blades you put on your own face. The Leaf’s low-tech, simple single-blade was cutting as closely and well as any fancy cartridge blade setup I’ve tried on the market. The reason was mostly that it was still sharp.

Because here’s the thing: It doesn’t matter if you’ve got a 15-layer stacked blade cartridge with whistles, lights, and responsive AI. Dull blades are awful, and all blades get dull with use. And when blades get dull, they start to yank on my hair instead of cutting it, irritate my skin into aggravation, and cause little nicks when the skin pinches up. Alas, the modern cartridge-based shaving blades that dominate the supermarket are expensive and often inconvenient to constantly replace: around $30 or $40 for a pack of 10.