Ask a collector and you'll get an in-depth answer on the feelings that are evoked, perhaps the investment made or the quest to find their stuff. Although collectors always hope their collections will increase in value, that's not why they started their collection.
My thoughts have always been if it's sold as a collectible, it's not.
At a recently gathering of authors and experts on antiques and collectibles, I asked the question "What is your definition of a collectible?" Rarely did anyone have a quick or glib answer but, after a few moments of thought, would come through with their definition.
A piece of a person's personal history that holds a special place in their heart.
Dean Jutilla, eBay
Something you can't get enough of. You get one, you gotta have more.
Brent Feigner, Playthings
A collectible is something made between 1963 - 1980.
Harry Rinker, Rinker Enterprises
You own more than two of something that you have no use for.
Denise, Doll Collecting on About
Something that brings you happiness.
Susan Peterson, Peterson Consulting
Part of a group of something that I want to own.
Peggy Kinstler, Informart
It's a focused and special way to connect with a part of life.
Jordan Wright, Planet Collector.
A collectible is anything that is non-essential that someone wants more than one of.
Useless stuff in lots of different colors.
Jane Viator, Antiques Roadshow Insider
Anything that wasn't meant to be and is.
John Bruno, Flamingo Promotions
Something that has an emotional connection to you personally.
Linda Kruger, Collector's News
Collectibles are things you collect.
Jim Tucker, Antiques & Collectibles National Association
Any object that has special meaning to a person.
Beth Deisher, Coin World
An item that's valuable to you personally no matter what the actual value is.
Cathy Clark, The Numismatist
Anything desirable that people are willing to pay money for (to add to a collection).
Pam Wiggins, Antiques.About.com
Something I must have to add to other like objects.