@dalehileman,
Because there were so many people running, the Republicans decided that only so many people can be on the main debate at the same time. Before each debate, they check the polls, and the highest polling candidates get the late time, the lesser polling candidate get the early, lesser watched time slot.
It is not a deliberate insult, but if a candidate was on the during the main, later debate, and is now on the earlier time, it is a pretty clear indication to the public that his campaign is losing ground to the other candidates.
Before the debate season, Rand Paul was considered one of the very top Republican contenders. Now he's on at the early time because he can't get any appreciable support. That's a big comedown.