Basically, a Sith wants to win at life. A Sith knows that life will continuously present challenges and obstacles to overcome, and a Sith usually operates best when under pressure to overcome such challenges.
To a Sith, every aspect of life is of a competitive nature. Sith like to secretly (or even openly) compete with those around him, including perhaps family, friends, acquaintances, colleagues, and so on. A Sith must be victorious no matter the odds. If the odds are against him, the Sith will work hard to turn the odds in his favor. A Sith does not tolerate failure in any form, whether that is failure of self or failure of others. A Sith loves strength and detests weakness.
Creating great success for himself in his own life is paramount, whether that, for example, is financial success and becoming a millionaire, or success in terms of developing powerful supernatural abilities. Sith are aware of and understand that creating a highly successful life requires patience and determination, and although Sith are generally not known for their patience, when it comes to their own life and their own self-interests, they can often have great patience, sometimes waiting decades, when they know that great power can be theirs, if they are able to persist until the end, and finally achieve the high goals they have set for their life.
Of course, there are some Sith who prefer to keep in the shadows, and have no desire for worldly success such as fame, millionaire status, or having power in society, but these types of Sith devote their existence purely to developing and deepening their connection with the Force, in the hopes of becoming all-powerful, and ruling society, or even ruling the whole planet, from the shadows and the darkness. And even if these types of Sith have no desire to rule over others, they simply have the goal of becoming the most powerful being (in terms of supernatural powers with Force) on the entire planet. I must say, I do have great respect for these types of Sith who live in the shadows and devote their lives to not only developing devastating powers with the Force, but also to understanding the Force at levels often far beyond what the average Sith living in society could ever accomplish.
Personally, as a Sith myself, I prefer a balanced approach to life, slowly developing excellence in the few areas that are most important to me. But just because I choose to live in society, does not mean that I cannot transform myself into a powerful demigod with incredible abilities and skills with the Force.
May the Force be with you,
Sith Lord Zanetti
Author of the bestseller Superhuman Training.
Here is one of my personal Sith videos speaking on the Dark Side: