I reckon it's probably just been a bit of a financial flop; it seemed to hinge on some notion that people would print a lot more once they were viewing it as 10p per page rather than £25 per cartridge but no one wants to have a pile of printed crap. I'm sure there's loads of people on those £1 plans who don't print for months and HP just have to keep sending out new cartridges after leaving the printer unplugged for months. In the past they were probably getting £30+ out of those people for the two cartridges once a year.

I'll be ditching the printer once I'm expected to pay more anyway.