Sterotypes

Stereotypes must be slightly true because they had to be true for a large number of a certain group for some time for them to become well known. For example the stereotype that Asians are bad drives i find to be quite true because I live in an area of San Diego with about 85% Asian population and 9 times out of ten that someone cuts you off or runs a stop sign is, you guessed it, Asians. now I don't think it has to do with race, i think it has to do with upbringing. Many of the drivers are first generation immigrants that's families never had cars and driving is a relatively new experience and the rules of the road aren't ingrained in them since the time they were born. So my point is are stereotypes completely wrong to assume?