Your formal schooling may be over, but your education never ends.
Statisticians, no matter how well trained, need to invest in continuing self-development. We are in a rapidly advancing field. Those who do not stay abreast will be left behind. In this way, statisticians do not differ from professionals in other rapidly advancing fields, such as medicine, biology, and computer science.
New methods and tools are being developed all the time. Those who received their formal coursework some time ago were, most likely, not trained in such areas as simulation-based inference, statistical learning theory, spatial analysis, and Markov chain Monte Carlo methods for Bayesian analysis, which are now part of the standard curriculum at many graduate statistics departments. In addition, there are numerous emerging applications—in such areas as biology and genetics, environment and ecology, atmospheric sciences, and Internet social networks—that were essentially unknown some years ago, and in which practicing statisticians are involved today. In the same way, you can expect numerous new technical developments that you will need to keep up with through the course of your career.
In addition, you will need to learn about specialized tools that pertain particularly to your selected application area and/or job that you did not study during your formal education, as discussed in Section 7.7.5. And if all of that is not enough, ...