I don't know who decided, "hey, we have these amazing books, let's turn it into a screenplay and completely change everything about the story!"
The original charm of the book wasn't preserved at all in the show. They basically took the name, changed everything, manufactured chunks of story that didn't exist and ignored relevant story line, then added a bunch of super cheesy special effects. I don't know who thought they could write better than Robert Jordan, but they were wrong.
The end result is slightly confusing, very bland and completely forgettable.