"Speed Kills!" is a popular road safety slogan that we hear often. It's pretty simplistic and when I look around me on the highway I am convinced that drivers either don't believe it or live in a world of denial. Speed alone doesn't kill, but combine it with poor driving skills or a bad decision and it definitely makes a bad situation worse.
The most obvious drawback of speed is that the faster you go, the more likely some road user is going to get hurt or killed when things go wrong. Energy increases as the square of the speed and our bodies can only deal with sudden changes in energy to a certain extent. Exceed that threshold and we tend to come apart at the seams.
The faster you go, the less time you have to deal with issues. These issues may be caused by you or they may be caused by another road user. Either way, if you are going too fast to react and recover, it's going to hurt someone.
"Go with the flow." Yes, I agree that is a good idea until the flow exceeds the speed limit. I like to obey the rules of the road and we have some drivers who are unsafe at speeds above the limit.
Perhaps the next time the news tells you that a collision was a result of speed, think that it probably means inappropriate speed made a driving error unrecoverable.