Open access is free online access, and is perfectly compatible with other kinds of access to the same content. A publisher of an open-access journal might lose money by producing a print edition of the same content, and this is one reason why some publishers might elect not to create a print edition. But a publisher might decide to sell a print edition for cost to those who need it, or prefer it, while serving most constituents through an online open-access edition. Since the open-access edition can generate at least as much revenue as is needed to cover its costs, and priced add-ons can generate even more, publishers need no longer see the print edition of a journal as the economic centerpiece of the enterprise. And of course, open access is compatible with printing copies for the purpose of long-term preservation, and compatible with users printing individual articles through their browsers.
I don't know why these eight desiderata of traditional journals all begin with the letter P (if we turn 'quality' into 'professional quality' and fudge with 'intellectual property'). But it does tend to make the virtues of open access easier to remember: if we adopt open access, we needn't sacrifice any of the eight Ps, and we get open access to boot.