If you miss a court date a bench warrant will be issued against you which is an arrest warrant for failure to appear. You will be arrested and asked by the judge about the reason for missing the court date.
You might also face criminal penalties like jail term and fines for deliberately missing the court date as this action of yours will be considered as contempt of court.
In case the defendant was originally charged for violating some traffic rules and he misses his court dates his driver’s license may be suspended.
If the defendant was initially released on “own recognizance” by the judge and he fails to appear in the court hearings, the judge may decide to set a high bail for the defendant who was released previously without bail.