When you're playing with an orchestra on stage, it's best to forget that not everyone in the audience is attending your concert willingly. Undoubtedly, some audience members are making calculations such as, "They're starting with an overture. That's a shorter piece, so that'll probably take about X minutes. Then, there's a concerto. That'll be somewhat longer, so X minutes for that. The last piece is a symphony with four movements, so that'll be the longest piece. I'll guess about X minutes for that. Factor in the intermission and applause after each piece and then walking to the parking lot and driving home...So, if I can function on a little less sleep tonight, I'll be able to watch the game I recorded before work tomorrow."
When I played music onstage as a teenager and young adult, I wanted to believe that everyone was paying rapt attention to every nuance of the beautiful Beethoven symphony our ensemble was playing. Deep down, I knew that wasn't the case, but I chose to stay idealistic nevertheless.