Amazon has some pretty strict rules for Sellers around customer service metrics. How long it takes you to ship orders, customers' satisfaction with the returns process, and other metrics are yardsticks that Amazon uses to measure your trustworthiness as a seller.
Failing to adhere to these metrics causes your Seller Rating to fall, something which might affect the ranking of your products in the search algorithm, and at worst, cause Amazon to suspend your product listings or even your account.
A key metric is responsiveness to customer messages: you must respond to questions from customers within 24 hours (yes, even over the weekends).
Today, Amazon announced an even more drastic update to this 24-Hour Rule: during the holiday period, Sellers must respond to customer questions within 12 hours.
Clearly the Holidays are a season when Sellers are not exactly falling asleep at the wheel; however this kind of requirement does add an additional burden to the management of your Amazon account.
To support our clients, we just updated our "Daily Review" process to be conducted twice a day. If you're managing your own Seller account, make sure you're prepared!
*Note: this post was written in December 3, 2015, and a few things have changed since then! Find the updated response times on the Amazon help page.