So yeah, it should be:

orange >= 100%
100% > yellow > 50%
50% >= green > 0%
0% >= grey

With the exception that the first yellow skill is always 100%.

You are however not the first person that I have seen mentioning this.. so might be a bug or a skinning unique thing?

Well it's not because I consistently don't get skillups from orange

Well it's not because I consistently don't get skillups from orange

Just to be clear, youre looking at the color of the skinning text "Skinnable" and not the level of the mob itself, which could be orange to you due to a separation in levels?

Yes

Have you checked that you are not max skill?

I've done this with all gathering professions incl skinning. I gather for like 10 mins and wondering why I don't get any skillups and I look at my skill tab and I see for instance that I have Skinning 225/225.

I've leveled Herbalism and Skinning (Herbalism on two chars) both up above 225 and I've never experienced this, unless I forget to rank up.

Sometimes I obviously continue leveling with max skill because it's either expensive at that level or I'm on a "roll" and don't want to get back to a major city.

I have 300 Mining on one char and ~200 herb/skinning on another char. If this happened to me I never noticed it.

I've got the same issue.
I was leveling skinning yesterday and when i was around 180/225 i did not always get a skillup on an orange colored beast.

I remember encountering the same while skinning a turtle, I was sad because it was killed by another player and was much higher level than I could kill. Could it be because your skinning is a bit ahead of your level? Were you skinning creatures that would be impossible or hard to kill by yourself? I don't know. :/

Edit: Hmm, it did not make any sense anyway since the limitations are already applied while learning the professions.

Not really, I was a lvl 60 killing 40-ish mob. And no my skinning wasn't maxed

I levelled to 203/225 last night and to skin several mobs before getting a skillup. I skinned everything from green to orange, it remained the same.

Just ran into that yesterday for about 3 or 4 mobs that showed skinning as orange. Hasn't happened since.

Apparently for skinning it's not like other professions;

Skinning Color Codes
Any skinnable corpse will have a a color code on the "Skinnable" property when you move your pointer over it:
Red: Not skinnable.
Orange: Difficult to skin, may fail; high chance of increasing Skinning skill level.
Yellow: Moderately difficult to skin, almost never fail; moderate chance of increasing Skinning skill level.
Green: Easy to skin, should never fail; low chance of increasing Skinning skill level.
Gray: Very easy to skin, should never fail; no chance of increasing Skinning skill level.
Up to skinning 100, you can find out the highest level mob you can skin by: ((Skinning skill)/10)+10.
From skinning level 100 and up the formula is simply: (Skinning skill)/5.

(source: https://vanilla-wow.fandom.com/wiki/Skinning )

It always cracks me up when skinning fails.

"Oh shit I fucked this leather up, it didn't come off right. Let's put it back on the animal and try again!"

It always cracks me up when skinning fails.

"Oh shit I fucked this leather up, it didn't come off right. Let's put it back on the animal and try again!"

I always imagined this as you accidentally stabbing yourself. "And just slice through the belly right h - FUCK THAT'S MY THUMB".

I always imagined this as you accidentally stabbing yourself. "And just slice through the belly right h - FUCK THAT'S MY THUMB".

oooooooooooooohhhhhhhhhhh....... that was MY leg that I just skinned................ I really feel silly now.