Let's elaborate with an anecdote: A woman called me one day demanding to know where the rest of the items in her order were. I tried to reassure her to the fact that we at ***** have the best outsourced customer service in the country and we totally give a shit about these purchases getting there in time for Christmas/birthdays/MLK day/whatever.
So after hearing her rant about how urgent it was she got these Vera Wang bathrobes or whatever, I asked her what her order number was. She gave it to me and I quickly searched for it in the program.
The woman had ordered around 40-50 items during a clearance sale.
"Alright Gin, don't fret, you can do this. Just copy the ID numbers in notepad and put them on a new order", I thought, while at the same time she kept chewing my ear off about what could possibly be taking me so long.
If you are in this situation; you are fucked, because you have to go through every single item on the list with the customer to see which ones got there, which ones didn't, which ones are broken/wrong color/size/fabric/etc. The discounts are no issue because under special circumstances, CS has special codes that never expire to make the discounts valid to a disgruntled customer.
But as I pasted each of the codes into the system and refreshed to check their status, I realized very quickly that more than a quarter of them were out of stock, and even more ran out of stock as I continued refreshing and modifying the order. So the conversation would detour to:
"Ma'am, I'm sorry about this, but item ******* is currently out of stock, can I instead interest you in [Fuck whatever else]?"
Followed by more complaints about what an irresponsible company we are, how we are assholes for not getting the items there (To this day my image of the people in charge of sending orders out is a room full of chimps because they fucked up often and nobody knew who or where they were), strings of increasingly creative insults, threats of legal action, and other fun stuff.
A call like this where one or two items are out of stock can easily stretch to 30-45 minutes depending on how pissed the customer is. Mine took 5 hours until me, my supervisor, his supervisor and the customer all gave up and just settled on giving her discounts for similar items in the future.
TL;DR: Retail online fucking sucks.