While I have not met Khatia Buniatishvili in person, I love her playing for one simple reason: She plays with great passion.
Many composers have struggled with a variety of issues: Depression, loss, unresponsive love, povery, illness, and more. All of these issues are expressed in a composer’s creations. And that is what makes these compositions great. As such, it is up to the performer to identify areas of the music where these feelings are captured and to communicate these to the public.
That is what makes a performance special.
Here is Ms. Buniatishvili playing the Piano Concerto #2 by Sergei Rachmaninov: