If I drive slowly the likelihood of spotting a forward collision early is higher and I have more time to react, and certainly the speed differential as I approach some stopped traffic is lower reducing my braking intensity. If I'm driving slower I can make the same radius turn with lower Gs improving that rating, and I'm also going to be much more likely to be following safely since at the lower speed I can be closer whilst still having a safe headway.

So basically every metric is easy to improve by simply driving slower.