Most insurance carriers offer a driver improvement discount for taking the course. According to the Texas Department of Education website, the insurance discount is usually around 10% and is good for 3 years. So, even if you have never had a ticket and don't intend to get one, taking a defensive driving course is still a good investment.
To qualify, you must not have taken a defensive driving course within the past 12 months, and you must provide the court with a certified copy of your driving record to prove this. Most moving violations, such as speeding tickets, can be dismissed by taking traffic school. To request this option, you must either appear in court or contact the court in writing. The judge assigned to your case has the final say over whether or not your request is granted, but if you have a good driving record this usually isn't a problem. Typically, the judge will give you 90 days to complete the defensive driving course.
Most of the people who take a driving safety course in Texas are there because they've gotten a traffic ticket. According to Article 45.0511 of the Texas State Code of Criminal Procedure, under certain circumstances you can have a ticket dismissed if you take a state-approved defensive driving course.