Since some people can't get passed trying to get revenge on others, success is the best form of revenge. An individual that succeeds can show everyone else that they're truly on the right path in life, but succeeding simply to inflict a revenge on someone isn't necessarily the best idea.
Depending on what kind of revenge is being discussed, success is a very good way to get revenge. When a victim becomes much more successful than people who were bullying that person, that is truly a great form of revenge. It is a form of revenge where nobody is harmed, which makes it perfect for the task.