I drive fast and I drive slowly at times

I've got one bad habit in driving. When I'm driving and someone is right behind my back and moves to another lane trying to overtake me, I'll let that one pass just half my car and then I will accelerate as fast as I can, not letting them pass too easily. Sometimes they just can't overtake me! hahaha That's when I'm satisfied. That's when I feel the victory even though it's just a small thing. hahaha