When you're moderating a debate with only three candidates, the least you can do is wait until all three are on stage before asking a question. That one basic idea escaped the moderators of Saturday's Democratic debate, and Hillary Clinton had to come in late.After a contentious hour of debate about foreign policy, Hillary Clinton, Bernie Sanders, and Martin O'Malley took a much-needed break, but when ABC came back from commercial, Clinton wasn't yet onstage. Rather than wait for the former Secretary of State to start the second half of the debate, moderator David Muir barreled ahead with a question about the U.S. economy.While it wasn't the most explosive moment in the night as a whole — those belonged to Vermont Senator Bernie Sanders on health care, economic inequality, and foreign policy — it's hard to imagine a debate segment starting without any of the other candidates. Clinton handled it much better than Donald Trump might have; she strode back to her podium and jumped back in.As befits Clinton's status as one of the only women to ever run for the White House, the Democrat broke new ground when it comes to presidential candidates and bathroom breaks. In October, Clinton joked with that debate's moderators about how long it takes women to go to the bathroom. This time around, it wasn't so funny.