That's one of the lessons that filmmakers Tim Walsh and Ken Sons learned while making their new documentary, "Toyland: Fun In The Making," which explores the underbelly of the toy world via interviews with the inventors and developers of great toys like the Slinky, Play-Doh and Twister.
"It's a heavy-duty, super-secret business where rejection is part of the game," Sons said. "Still, to be around all these toy inventors who had created the games I played with while growing up -- I always had a Slinky -- was surreal."
His partner, Walsh, was already familiar with that part of it, both as a creator of games, like Blurt and TriBond, and the author of toy history books, like his current book, "Wham-O Super Book" (Chronicle Books), a history of the company that gave the world the Hula Hoop and the Frisbee.
Walsh says it takes a certain type of person to be a toy creator.
"They are not typical people. They think outside of the norm" he told AOL News. "Eddy Goldfarb, who created the wind-up chattering teeth in the late 1940s, saw an ad for something designed to hold false teeth and laughed. For some reason, that inspired him to create the chattering teeth."
Meanwhile, Kay and Bob Zufall, the developers of Play-Doh, came up with the idea after reading an article about alternative uses for wallpaper cleaner.
"They took an obsolete product and found a new use for it and took it to their brother-in-law who was in the toy industry," Walsh said. "He took the idea -- and the name Play-Doh -- and they never made any money from it. I think he took them on a trip."
However, he said they aren't sad about being ripped off.
"They did pretty well for themselves," he said. "He's a doctor and they live on a beautiful estate and they opened up a clinic in Dover, N.J., to provide medical care for the less fortunate."
Some others didn't do as well, such as James Spinello, who invented Operation back in the late 1960s.
"He took the game to Marvin Glass, who was the biggest toy designer at that time, and was paid $500 and the promise of a job when he got out of college," Walsh said.
That job never materialized, nor did any royalties.
"Surprisingly, he's not bitter," Walsh said. "When we premiered the film in Sarasota, Fla., you could hear a collective groan when he mentioned selling the game for $500, but he collects everything with the game and is very proud. He said the best moment was when a woman told him her son became a surgeon because of that game."
Walsh was also impressed by the attitude of Milt Levine, who as "Uncle Miltie," created the original ant farm.
"He has a great line," Walsh said. "He tells people, 'People are impressed that an ant can lift 10 times its own strength, but I'm more impressed that they can put three kids through college.'"
Not every toy inventor has that kind of happy ending.
Richard James created the Slinky with his wife, Betty, but ended up joining a religious cult in Bolivia where he spent his last years, leaving his wife to run the company, which she did with great success.
"At first, I wanted to interview the creators of these toys -- the rock stars of this industry," he said. "Everybody knows the Slinky, but don't know that Betty James developed it with her husband, Richard. They don't know Reyn Guyer created Twister or the Nerf ball.
"However, it became apparent we didn't have an outcome. It was just me interviewing one old guy and then another. So we decided to include the development of a new product I'd been working on and show me trying to sell it."
That product started out as a game Walsh developed while watching his kids decorate their chins with funny faces. He envisioned it as a card game at first, but also thought about turning it into a face painting kit.
"He also gave me some other great advice: He says the best toys break a rule. For instance, you don't throw a ball in the house, but that's exactly what you do with a Nerf. You're not supposed to invade personal space, but that's what makes Twister so fun. That's why he liked my game Blurt so much -- you're supposed to raise your hand, not blurt out the answer."
"It was a little awkward having that be filmed, but while Hasbro rejected it, their executive Mike Hirtle was willing to offer advice about toys in general," he said. "He also conceded that he's been wrong before."
Walsh was ultimately able to sell his product, which is now called "Crazy Chins," to a face painting company. "It's been scaled way back from what we originally planned -- which is not uncommon. This is an industry where you have grown men and women deciding what kids like."