Avon's problem is its inability to adapt and change. It's original business model lost out to other start up such as Mary Kay. It ventured into "mail order" which is a disaster for cosmetics. Then it could never balance its retail sale force with retail store sale strategy.
Especially with the rise in popularity of stores like Ulta and Sephora.
Avon really missed a huge opportunity by not negotiating space in these stores to promote their product to the new generation of customers.