That is part of it but as I see every day driving into work there are people driving too fast for the conditions and darting in and out of lanes.  I actually almost saw one happen this morning driving in on I-25.  People think that driving crazy will get them to where they need to be a lot faster when in reality they MIGHT save 5 minutes.  Compare that to the risk of death (yourself or someone else) and it really is not worth it!