* The magic number is $40. If you send a large box of clothes to them, they will pay you some amount that's very near to $40. That's the amount that stops you from complaining.

* They effectively sell 6mm SKUs because almost every item is unique. This makes efficient logistics key. They used to operate out of 2 warehouses, and they would charge the same for shipping from either warehouse, until some engineer pointed out that they would actually lose money if the customer ordered a low value item from the warehouse farthest from them. So then they shifted to subtly only show/promote you items that are located in the nearest warehouse to you.

* Customers typically browse ThredUp while waiting in line. This is something you do to fill the time, like Twitter or Facebook. They find most purchases are impulse and average time on site/app is very low. This might be why growth isn't as good right now

However, the turnaround time has gone to hell. You can ship them a box of clothes and they won't open it for 6 months. An ever-increasing net loss and they can't keep up? Not a good thing. They better figure this out.