[Zeke]

Exterior finishes are available in satin and semi. What is exterior? Just good paint. You can often find interior/exterior which is nothing but marketing in my mind. One size fits all. There may be additives that help with exterior exposure, but what they are really doing is saving shelf space. What you need to look at the amount of acrylic and the percentage per unit. So, for instance, porch and patio paint has a high acrylic proportion. That kind of paint is typically on an outside horizontal surface and subject to foot traffic. Good paint. Not cheap because acrylic resin is one of the more expensive ingredients.

Cheap paints rely more on vinyl and latex rather than 100% acrylic. And there's more: 100% acrylic, but at what ratio to other ingredients? It gets complex. You have to dive way deeper than a label. Or just consult with a knowledgeable paint supply.