I was a big fantasy reader in my teens already, and read Elantris when it was the only book published by Brandon Sanderson.
I liked his style and over the years read his newest books not long after they were released. I was happy when he was chosen to finish Wheel Of Time, because that was another favorite series of mine, although I liked the writing style of Sanderson much better than Robert Jordan.
I somehow went through Mistborn, Stormlight, Warbreaker and even some of the novellas without connecting the Cosmere thing.
Then via subreddits it finally clicked and I chose to do a big reread of everything Cosmere. Almost done, only the last two Stormlight books are missing. And of course the newest secret novel.