The day-boundary is arbitrary. It encourages someone who gets stuck on something at 2pm to spend the rest of the day banging on it and bring it up tomorrow. Or, in better functioning teams, we deal with it at 2pm and the standups become irrelevant. That was what I found.. is that as a team lead I knew what everyone was doing before we met in the morning. Another popular tendency is to pull in PM, or maybe my boss.. but then I get to waste 6 people's time trying to communicate what's happening to them on a still-arbitrary schedule.