An observation about "Modern" classical music.

As I sat in my car, waiting for my wife as usual, I listened to a local classical music station which happened to be playing some "modern" music. I don't like it, being an old fart who likes Mozart and his ilk. But, as I had nothing else to do, I tried to appreciate what I heard. No luck, but I did notice something I have experienced before but never thought about. At the end, there was a dead silence of 3 to 5 seconds before audience applause. This never happens with, for example, Mozart where the final notes never get a chance to decay before the applause and Bravos. Obviously (IMHO) the music was so hard to "follow" that the audience were not sure it was over until nothing happened for a while.

I know that some guys like this music, but haven't you noticed this dead time? How do you explain it?