The statement argues that the term "success" has only one meaning: the ability of using your time in the way you want. The passage makes the reasonable assumption that feeling good with yourself is sufficient for having success in your life. However, the fact that success is related only to the way life is spent may not be valid for everyone.
Let us make the example of a manager in an important firm: for him, success may not be determined by how he conducts his life: first he may think that the ability to take the right decisions, to be respected by other employees and to maintain the leadership of his group are the main factors for success; however, if he reaches the goal of conducting his life in the way he wants, he can maintain (not gain) the success achieved.
Another example could be that of a farmer, who is happy to do his job and does not have to deal with anyone but his fields and his family: for him, achieving success may mean spending his life in the way he wants.
In conclusion, the statement makes an inaccurate generalization. Success can not have a single definition for everyone, and the one in the passage above may fit for particular categories of people, such as those who do not need to adapt themselves in order to achieve their goals.