It did not seem that removing the rotor was related to wheel removal from the axle; rotor removal was done after the wheel was removed. Rather it appeared to be done prior to tire exchange and balance of the wheel. The video did not explain the reason for rotor removal just the difficulty on re-mounting the rotor to the wheel after tire exchange. I was perplexed too.
Dunno about people doing this job for themselves, but I've seen quite a few 'professional tire technicians' do the same generally needless disc removal thing...
Because the disc rotor stands out on the hub beyond the rim, many operators are 'scared' that their tire removal/refit machine will either be impeded by the rotor, or the machine's arms will hit & maybe damage the rotor, so they take it off. That's maybe not surprising, after all, they are being careful not to mark up &/or damage your rims, and besides, every other car rim they work on
DOESN'T have the rotor bolted to the rim hub, so it's an obvious conclusion - operator thinks "
Ooooh, there's a rim bolted to the hub??! Gotta take that off so the rim is naked just like everything else I work on!!" :lecturef_smilie: However, if they actually
LOOKED at how their machines work, and thought about it for a liddle bit, it should be fairly clear that with some care and the disc mounted side of the rim facing
UP (or
OUT, depending upon their machine.

) that the disc won't be in the way for the removal/refitting of the tire, because the machine works
on & outside the bead edge of the rim itself - there are very few modern machines that still have arms that use a shaft thru the hub centre to provide leverage.
Still, then there's the 'balancing' to take into account, and again,
most 'general automotive' rims
don't get balanced with the disc in place (there are a few 'high performance' exceptions, & a couple of other 'oddities'

) - so the obvious 'first thought' of that highly trained tire tech is to 'remove the disc'..... but then they find the bearings inside the hub & the small dia axle shaft hole, and realise they don't have the 'right' sized flanges for their balancing machines anyway! :sour: So
THAT's when they tell you they can't balance the wheel, and they just keep schtum about how taking the disc off was not necessary and actually a bit pointless right from the outset!! :gaah: