All revolutions will have an advanced, middle, and backwards selection of the population. Whether this advanced section is formalized into a party and thus democratized and organized, or left to form naturally, opaquely, and without accountability, the advanced segment will exist regardless. We can see throughout history that it is far more effective to formalize this segment to make it accountable than to let power structures form based on friendships and cliques.

I recommend reading The Tyranny of Structurelessness. The Vanguard model has consistently been proven to be the most effective means to wage revolution.