Pretty path:
Pubmind | tiers | transformation | convenience | author vs audience

Pubmind's tiers measure the amount of transformation that has occurred from personal notes to public publication. Publication medium has some correlation to effort invested.

T1 = Finalized format. True publishing, in which format and thoroughness favor the reader at expense of the publisher's team. Most bestseller books and movies are T1. A mature website such as Wikipedia is also T1.

T2 = Edited text in a developing organization. E.g. polished blog posts arranged chronologically, when chronology isn't the canonical organization for the topics discussed. Hierarchical sites that evolve content for eventual publication in a different finished format. Scripted and edited video. Whether the author intends to improve the format or not, the possibility of doing so makes it T2 rather than T1. Format still conveniences the author rather than the reader, but not overwhelmingly.

T3 = untouched rough drafts organized chronologically. Dedicated rough drafts blog or vlog or a chat "scratchpad" channel are the best mediums for T3. Blog is for longform and chat is for medium-length. The author lazily spams his thoughts to gain the benefit of self-conscious improvement and maybe some immediate audience feedback, and to keep his audience roughly informed of his progress, without guaranteeing quality or accuracy.

A new zettelkasten with a few notes might be T1 if the author is carefully sourcing from a T2, or it might be a T2 if it's sourced from a personal knowledge base, or it might be a T3 if the author merely dumps his thoughts and timestamps them.

Think of Pubmind tiers as city tiers, the personal knowledge base as the countryside, and the thoughts as people. People travel from the countryside into cities. The more people concentrate, the higher the city tier gets. In the same way, thought density increases as Pubmind tier increases. At T1, myriad thoughtful organizational and presentation decisions have been made to facilitate communication of carefully selected and polished key concepts.