I'm just confused

I saw this as an ad on my GR home page and I'm confused:

 

 

The author is listed as Jennifer L. Armentrout writing as J. Lynn. Why two names? Why are some of her books by her full name and some by J. Lynn. And if she's trying to keep them separate why put them both on the cover? I'm confused. Why not just by J. Lynn.

Furthermore, how is a self-published book a #! NY Times bestseller?

 

I'm not hating... I haven't read it... it very well could be totally awesome. I would not know. A lot of my friends have read all of her stuff and love her.

 

I have read one of her books. My friends all gushed (Seriously, it was embarrassing. It was actual gushing) over it and I was dumb founded because it was so poorly edited and just, well, to be frank, bad. I didn't like it at all. But my friends' comments were about how they were overlooking the bad writing because the story was so good. Um... not to me it wasn't. I read the book in March of 2013 and I didn't like it so much that I refused to try any others by her. Of my friends who read this book, 90% gave it 4-5 stars.

 

Anyway - I'm not here to give my opinion about this author's writing. I'm not here to bash this author (although GR authors who write their bios in third person and try to be witty usually fail. Just sayin'). I don't know enough of her work to speak about it knowledgeably. And I'm not even here to hate on my friends who love her (although, I might rethink our relationship. HA HA HA j/k sorta ok not kidding). 

 

I am here because I'm confused. 1) Why the dual author names on the same damn book and 2) how are self-published books number one on any bestseller list that I used to trust. NY Times has let me down quite a lot in the last couple of years. BIG TIME!!!