How to define success?

On the campaign trail today Mitt Romney attacked Rick Perry's view of social security by saying, "You can tell social security has been a success by the number of people who depend on it."

He was responding to Rick Perry's assertion in his book that social security is a failure and should be handled by the states instead of the federal government.

Rick Perry said Romney is sounding more and more like a democrat.  And while I have supported both Romney and Perry in the past on various issues, I have to take the side of Perry on this one. My reason is because I do not define success the same way Romney does.

To me, success is defined by how many people don't depend on the government.  The fact that people depend on social security does not define it as a success.  Success is being able to retire whether you get social security or not.