Willingness to Be Wrong Without Defensiveness
The final condition is the hardest: you have to be willing to be wrong about what's good without defensiveness. Taste develops by testing it against reality. You see something and think it's good, and then you find out it doesn't work. Or you see something you dismissed and watch it have impact. Or you develop your taste in one direction and then encounter a different standard that opens your eyes.
The wrong response to these moments is to defend your original judgment. "I was wrong because I didn't have enough information" or "that piece worked but it's not really good" or "my original standard was right for that context." These narratives have the advantage of protecting your ego. They have the disadvantage of preventing learning.
The right response is harder: "I was wrong. Here's what I missed. Here's what I need to pay more attention to." This response requires actually sitting with the discomfort of being wrong—not as a mistake to explain away, but as a signal that your taste needs to expand.
This is why taste develops slowly, and why it's earned rather than given. It's built on a foundation of being wrong, and looking honestly at what you were wrong about, repeatedly, over years. People with excellent taste have been wrong a thousand times. That's not despite their good taste; that's how they developed it.