I don't really think Bionicle "went wrong" at any point, but 2001-04 was the only period I followed. I was 14, and I ignored Bionicle until the Bohrok saga. Technically I bought a couple of the McDonalds figures in fall 2001, but I didn't get into the franchise until issue #4. In 2004, I was 17. There was no "Lego Movie" back then, and it wasn't cool to play with toys as a high school senior. Metru Nui was cool, but I wasn't really invested in a prequel and I just let Bionicle escape me until I started reading the chapter books in 2011. For me, Bionicle became hard to follow in the prequel era. I lost interest when the story stopped moving forward. "Legends of Metru Nui" was awesome, but I missed the Toa Nuva and I didn't feel like waiting years to get the next real chapter in the saga. Now I am back catching up.