The arrows next to your B-spec drivers are generally considered to represent either their current mood or form.
They can be either Orange and pointing down, meaning your driver will not be at his best, Green and pointing sideways, which is neutral, or Blue and pointing upwards which is the one you ideally want to get the best out of your driver.
They can change for many reasons, such as being used too much or too little etc.
When one of my drivers is Orange, I tend to rest him for a few races, until it changes to Green, then I'll start racing him again, and usually after a few more races it will change to Blue.
Of course, if your driver is in an over-powered car, then the colour is irrelevent!!
