You're looking at the wrong side of the meeting. It's the time before the meeting, not the time after.

I like morning stand-ups, but a big problem is that if the stand-up is at 9, I start winding down whatever I'm doing around 8:30, and I don't start new tasks after 8-8:30. Multiply the loss by the entire team every day and that's potentially a big loss of time. And because everyone's schedule is different, there's really no place to put the meeting that avoids the problem.

The benefits of a well-run standup can outweight this productivity cost, but it's a real cost that needs to be considered.