When I was in law school, a billion years ago, we learned about the "reasonable person" concept. Here's a simplified version of it:
Imagine you are walking home from work. One the way you see a person crossing a railroad track. The train is clearly coming. It hits the person. He dies. The family of the deceased sues you for negligence, arguing that you should have tried to save the person.
Part of the way that case could be decided is by applying a reasonable person standard, meaning is it reasonable to expect an average person to intervene in that situation.
What makes the standard useful is that it forces people to ignore the outliers. There could be incredibly brave people who would risk their life to save that person. There could be people that not only wouldn't try to act but would enjoy the carnage. Neither one of them is the point. The standard requires you to focus on what is reasonable.
I find that standard useful in my world of the arts. For example when we were building a custom website for a production I didn't ask myself "Do I like this website" because frankly, who cares what I think.
I asked myself whether a reasonable arts patron would find the website attractive and functional.
That forced me to ignore the hypothetical patron who hates the web and finds the Google search page to be too complex.
It also forced me to ignore the super tech savvy patron who might find the site flawed because it doesn't properly integrate Instagram and Snapchat.
It's a perspective that forces you to "step into the shoes" of the majority of your audience. And that can lead you to making positive additions or subtractions that will make your marketing something special.