One Opportunity
Despite the fact that they were otherwise capable of moving very quickly, they were slowed down by something despite the fact that they could have moved very quickly otherwise. It was the busiest hour of the day, right in the middle of it! Ricky made a concerted effort to sidestep the approaching traffic, which he was eventually successful in doing so despite his efforts.
However, in the end the traffic made it so that they were completely unable to move in any way, shape, or form. Ricky was aware of only one window of opportunity to reach the hospital in time, so he needed to move quickly in order to take advantage of it.