Agree with it being a pattern issue that raises the flags - BUT - if you were arrested and spent the night in jail then it was probably more serious than JUST speeding; meaning they wouldn't just arrest you for speeding - but reckless driving is a different matter and it is more serious than JUST speeding.
FWIW - I remember a cop telling a friend of mine that got stopped for speeding once in Suffolk, VA that he was going to write the ticket for 19 mph over the speed limit because if he wrote it for 20+ mph over the speed limit then he would have to arrest him and impound the car.
True or not? Who knows - but he didn't speed anymore on that highway heading to work so it had the desired effect!

USMCFLYR