There's a saying that Mariah recorded Memoirs to get her mind out of her miscarriage back then.
Remember how Bye Bye has that wierd ultrasound-like effect on the intro?  That was supposed to be her child.  But she had a miscarriage, so she had to record Memoirs just so she can move on 
 
You may not know this back during Memoirs.. she was so stiff, and she wasn't like her.. now that I look back.. there really was something going on with her.  It looked like she was dealing with something bad.