The artist is looking for something subjective, something deep inside themselves (or not that deep) that applies to them, and few others. It’s a window into their soul. At best, it can be beautiful, it can approach the transcendent. At worst, this is why so much art is so insufferable: you don’t really want to look into some people’s souls. (By the way, art that is therapeutic/cathartic should probably stay in your closet: don’t assume that memory of your dad in his underwear is a worthwhile basis for art.)
The designer is looking for the objective, widely understood values (widely understood in his tribe, anyway). He’s looking for an easy entry point for the people he’s seeking to serve, and he’s committed to serving their needs, not his own. If they don’t understand, he needs to work to help them understand. He’s humble, he can’t look down his nose at people like an artist is often tempted to do. If his work frustrates or confuses the audience, it’s his fault.
They’re not exclusive, you can be a designer in one moment and an artist in the next. But you should answer for yourself: what kind of work do you want to do?
Do you want to “plow the fields of your own heart”, or dedicate yourself to the needs of others?