Not sure what you mean by "pracise my faults". If you mean work on your faults, then this is exactly what you should expect. Martina Navratilova (the famous tennis player) had a very good saying - "you're only as good as your weakest shot". So work on the weakest aspects of your dancing.
Here's an analogy. If your car wouldn't start reliably because of a problem with the battery, what would you ask a repair man to work on - the headlights?