The latter seems more plausible to me, but either is just speculation.The end result, though, is that there are rarely issues with Apple graphics drivers & regular software or games; again speculation, but for games I imagine they write to a pre-defined rule-set, rather than try to constantly be pushing the boundaries.(Mac OS X NVIDIA drivers are only available for Quadro-series boards, tho'.) Indeed, this is true even if you're running Windows under Boot Camp...

apple updating boot camp video drivers-48

It seems an odd turn of words to state that an operating system "requires" updates...

Apple makes its own drivers & they are included in the OS updates.

As far as I know, this is not true of AMD and Intel.

In the case of your Retina Mac Book Pro with an Nvidia card, there's beta support with Nvidia's latest drivers.

As noted elsewhere, NVidia themselves make OS X drivers for Quadro cards but these are aftermarket cards anyway, not supplied in any Mac build option available directly from Apple.

Apple provides core drivers, currently up to Open GL 4.1 or 3.3 - depending on your card, of course - plus legacy drivers for OGL 2.1 compatibility.

You'll also be able to update the driver from there.

A good reason to try out Nvidia's driver be if you use your Mac for gaming, or you run any other apps that use Open GL.

Link to Open GL support by Mac model have their own release for certain Mac GPUs - this is the current driver as of December 2015 However, they are predominantly for the Quadro series of aftermarket cards rather than default cards supplied by Apple.

There is also support for some cards which have been legacied by Apple - namely the Ge Force 680, 285, 120 & 8800 There is mention of beta support for some recent mobile cards, presumably as Apple are dropping legacy support on these in favour of AMD in the current lineup.

You mentioned NVIDIA: here's the link to the drivers available for download.