Cotton-poly blends are great—they're soft, breathable, and don't wrinkle as much as pure cotton. But that polyester content comes with a price: it's more prone to stretching than a full cotton shirt. You can't have both the easy-care benefits and the bulletproof collar of a heavyweight 100% cotton tee.

So you have to pick your battles. If you're wearing your tees mostly at home, where you're lounging around and maybe sleeping in them, the neck gets stressed differently than if you're wearing it out. At home, you might not notice a slightly loose neck as much, but it's still annoying.

The workaround is simple: treat your cotton-poly tees with a little more care. Wash them like they're delicate, even if they're not. That means cold water, gentle cycle, and low-heat drying. It's extra steps, but it keeps the collar looking right.