Lack of usability costs money

I needed a cartridge for my printer, and it all started well: the printer has an embedded webserver with a page displaying a button "Order supplies". I decided to give it a try.

Clicking on the button asks you if you want to send the printer information to HP so you don't have to enter printer details yourself. Great idea, there's no risk of error here!

As to spread sending costs over several cartridges, I decided to order 2 additional colors, which brings the total of 3 cartridges.

Until then, all went very well, and now HP will redirect me to an online shop, a partner of them. They actually let me choose between two shops, and I choose the cheapest. The problem is that when they transfer your order to the shop, they online transfer 1 product, and you're supposed to search and select yourself the additional products in the shop's products. Why? Didn't I already do that earlier? Why introduce a risk of error that was avoided earlier?

I gave up ordering, I'll do it another way.

HP will certainly not care a lot, I'll have to get the cartridge anyway (refills for these cartridges don't seem to be widely available at this time. The best I found was a kit with empty cartridge and refill ink, but costs 140$, or this one for the C7180. I'll keep these option for later). But the partnering shops should, as they're loosing sales. Mine at least....