Meaning: People who keep trying and never give up are more likely to achieve their goals and be successful.
Choice of Words: The word "success" means achieving your goals or doing something well. "Comes" is used to show that success is the result of someone's actions. "Those" refers to people who have a particular quality, in this case, those who never give up. "Never" means not at any time, and "give up" means to stop trying.