When u can truly define success according to what you want it to be and not by what others tell you it is, u would have "achieved" success already.
The guy who wrote WTF? 23 properties by 30: A Story of What/When/Where to Find was already a success looong before we all call him the success that he is today! The first few years When he was working in a bank, he did not own a car. All he had was a motor bike. The savings he got riding a bike instead of getting a car loan were wisely invested in properties. Had he cared too much about how his peers would have perceived him, he would not have been the "success" that he is now. In his world, he would probably say, "WTF? I was a success long time ago before anyone even realised it back then!!!" And I say good on him! Because not many young people would have thought like him and that includes yours truly.