The Focus of the Dark Side
Unlike the Light Side of the Force, which embraces the whole, the entire focus of the Dark Side is the self. The appeal of the Dark Side is its very destructiveness and its isolation. Those who seek power for selfish reasons find comfort in its narcissistic gaze. The Dark Side emphasizes aggrandizement of self to the exclusion of others. In this way, rage and anger are turned into sources of strength.
Many are attracted to the Dark Side because its selfish nature allows great and showy deeds. The ease with which power is summoned belies its danger, for anger and hatred consume the individual even as one dominates one's surroundings. Ultimately, the Dark Side rejects the very celestial nature of life itself. To the Jedi, the Force is not a part of their existence, it is their existence. To a student of the Dark Side, this is incomprehensible.
It is not uncommon for Dark Side students to go into the wilderness, much as their Light Side counterparts do. The crucial difference is that the Light Jedi goes into the wilderness to commune with the wild. The Dark Side follower goes to separate himself from the community of life. There, in isolation, a Dark Side follower can perfect his or her own oneness with the Dark Side, and revel in that corruption. Yet in the Dark Side are anger and hatred and isolation and... fear. That fear drives the Jedi to isolation, jealousy and desire to be the most powerful of all.
This very predatory nature sparks battles of dominance when several Dark Jedi or Dark Side Adepts gather. Sometimes these are violent confrontations, other times they involve subtle mind games or diplomatic discussions, but make no mistake, there will be some attempt to assert control over each other. The violent nature of the Dark Side often leads to betrayal and bloodshed.
Not only does this fratricidal tendency discourage long-term cooperation among Adepts, it has also hindered the passing of knowledge. Whereas the Jedi and other servants of the Light Side have established great libraries and oral traditions to advance their work and educate succeeding generations, those of the Dark Side have few such institutions. Many never record their knowledge for fear it may aid an enemy. Others are too arrogant to allow others to learn from their mistakes.