How to organize the layers of vector files

In all cases, I label document & layers with a brief & understandable name.

• I stack layers in a logical sequence top down, i.e. left-handlebar, right-handlebar, hand-grips, headlight, seat, front-fender, rear-fender, front-wheel, rear-wheel, left-peddle, right-peddle, etc... 
• I put related layers into groups and label the group, i.e. "ALL-handlebars, ALL-peddles, ALL-wheels..."

I think you get the idea.

This is as much to keep me organized when I'm working with 10 or more layers as it is for Stock customers who eventually buy it. 

Hope that helps.

So I mostly work with vector files and checked the "Vector Requirements" on Adobe Stock Contributor. So in the requirement under the "Organizing your layer" section, they mentioned, "Don't include all assets on one layer or in one group". I attached the Screenshot. So I want to know are they talking about Layers or Sub-Layers?

By @RichGraphix

They are talking about organizing your assets in such a way that someone licensing your asset has the least problems opening it and working with it. So they are talking about both!

This is an example of a bad layer organization:

This is better:

(You should preferably not include a background, if you want to give the buyer the additional choice of PNG files)

For such requests, best is to use inline graphics here in the fora. That allows people to see immediately what you want to do, without the need to click around. 😉