What Makes a Performance "Authentic"?

Dear Viola family!
“Authenticity” gets thrown around a lot in music—but what does it really mean?
Does it mean following the composer’s intentions? Staying faithful to a style? Being emotionally honest? Or just sounding convincing, no matter how you get there?
👉 In your view, what makes a performance feel “authentic”?
Have you heard (or played) something that felt totally real—even if it didn’t follow the expected rules?
Curious to hear how you all define this elusive word.