Amazing read. And I recall when I first saw 99 dresses how much I recognized the need, where my wife has literally hundreds of dresses and doesn't wear much multiple times.
On mobile but will elaborate on this as I think the idea was amazing but could have also benefitted from something specific...
EDIT:
My wife as a great style sense - and also reasonable with her money. She would find amazing fashions at Crossroads in San Francisco where she could find desirable brands like D&G, BCBG and other smaller labels where women sold their designer clothes at a discount.
She picked up MANY amazing dresses from this place, as well as shoes. She hardly recycled dresses for events or dates and did it economically.
If 99Dresses had coupled with places like this where they had rental inventory as well, I am sure this would have been an amazing offering.
You could have had a daily rental price, as well as an option so that if the owner chose; a sell price.
A place like crossroads was actually pretty good at being discerning, yet well priced in their garments.
It would also had been an opportunity to provide brick-and-mortar fitting rooms... as well as local inventory. Connect this with a garment style ID and a "different sizes available via online at locations X Y and Z.
DISCLAIMER: Did 99Dresses have all this already?
I am amazed it did fail - I LOVED the BM and Idea.