I mean, when the red traffic light and red tail lights both mean stop, it makes sense. When the amber traffic light and amber turn signal both mean caution, it

I mean, when the red traffic light and red tail lights both mean stop, it makes sense. When the amber traffic light and amber turn signal both mean caution, it makes sense. When blue means "emergency vehicle" and green means "go" when driving, co-opting a similar color to serve a different purpose goes against the intuition that all US drivers have ingrained in them over years of driving.