There's having to get on AliWangWang and chat up sellers to make sure they actually have stock of the items they're listing for sale. If you optimistically order without spending ten minutes going back and forth with them beforehand, your purchases may not ship because one of the items is out of stock or no longer available in that size/color (despite it being listed w/claimed inventory of 9898998 pieces in stock) and when you do get on WangWang, you've got to waste more time haggling over individual item cancellations, substitutions, etc.
And even if everything you want is in stock, you're lucky enough to be ordering when the seller isn't away from their phone/computer because they're asleep/eating/whatever and so is available to confirm this, they're as likely as not to wait until a bit later to confirm your shipping address. If you're not on WangWang to respond to the shipping address confirmation query, then your order sits around unshipped until you do (and until they read your confirmation).
When you do receive your purchases, you can expect them to be cellophane-envelope wrapped or rolled up in clingfilm, which is usually sheathed in a layer of Mainland grit and grime (hence the cellophane/clingfilm) and this in turn is often packed in crumpled Chinese newspapers or scores of the foam webbing collars one sees used around individual apples, pears, etc. in supermarkets here.
If you live in China or HK/Macao, then you'll probably use Taobao much more than Amazon, but only because of the shipping costs. Actually enjoying using Taobao after having used Amazon, though, would require a strong masochistic streak.