I think a shared visual content (own artwork or favorite) is an image that matches your likes of views and that you're proud of that content and sharing it in the open virtual space in front of strangers is important to other's to enjoy or learn from it.
I actually use collections as a sort of all-catch for things I want to comment on at a later time, artists to check out later, and sometimes as a "Watch Later"-list substitute.
Sure, it wasn't intended for that, but --
I used to clutter my browser with literally thousands of tabs - as in, I still have 3180 open right now - just to keep track of things I might want to check out later, write a comment on, or where I was not quite sure if I should place something in my favourites or not.
Not anymore, now I've got "Temporary Collections" for that.
i like making for myself and for other people, but i never do art just for me or just for other people()except some pathetic sketches that should have been burned and left on the darkest side of my mind), to show to the others, first i have to like it too.
I use my favorites folders as my collections I love looking back on all the art that makes me smile! I know that somewhere when people check out their art in my folder they too will find something else they may like.
I do that when people favorite my stuff. Check out their collections and find a whole variety of related cool stuff