He Made The Decision To Interrupt Her
It’s possible he didn’t hear her correctly or was attempting to shift the conversation’s focus. Attempting to autograph the Big Apple sculpture in her hands, he was stopped by her and informed that “No, I don’t need you to sign anything.” She stated.
Before she smashed his sculpture in front of the whole gallery, she had a brief conversation with him. There’s no doubt about it, he was ready to listen, as well.