Gen Z cat lovers don't just believe in the cat distribution system − they spread the message via memes and T-shirts.

Stories of the so-called cat distribution system seem to propel the phenomenon forward: When the universe presents you with a stray cat, many people opt to take the furry creature in, foster or permanently adopt it, and the rest is happily ever after. Lore surrounding the 'system' is what turns many a pet-free household into a warm, safe, loving forever home for stray cats and orphaned kittens across the country.

"I never would have known how much I loved cats until a cat forced itself into my life," Tina Fried, the senior director of ASPCA's Los Angeles Felines Programs told USA TODAY. "The cat distribution system is a way for cats to make their mark and let people know how awesome they are."

But those stray cats don't just come out of thin air. Animal welfare experts may love the 'system,' but approach it with skepticism, Fried said, because not every cat or kitten that's outside needs to be, or should be, taken in as your pet − or taken to a shelter, in some cases.

"I think people are misjudging what the universe is telling them when they find kittens outside," Fried said.

What is the cat distribution system?

It's much more common for dog owners to have gotten their pup from a breeder or a shelter as opposed to directly from the street, said Will Zweigart, executive director of New York's Flatbush Cats, a nonprofit working to reduce the stray cat population in Brooklyn.

Across the U.S., if someone wants a cat, it could seemingly come from anywhere: The junkyard, the grocery store parking lot, underneath an abandoned car − making a trip to the animal shelter unnecessary for those who receive their cat allotment through other means.

But the reality behind the magic of the cat distribution can be grim: There are so many stray cats in the U.S. that the ones who make it to shelters are a small sliver of the population, Zweigart said.

"There are far more cats being born and looking for homes then there are available homes," Zweigart said.

The downside of the 'cat distribution system'

Fried and Zweigart said they don't fully believe in the cat distribution system because the phenomenon can cause more harm than good.

Too often, Zweigart said, a cat that already has a loving owner will get scooped up by someone who's a little too excited about getting their allotment from the cat distribution system.

"I wouldn't want someone to see a cat and think some larger forces are at work and accidentally steal their neighbor's cat who's perfectly fine," Zweigart said. "Particularly if you don't live in that area, you need to be very careful about just scooping up any cat."

With kittens, Fried said, one of the worst things you can do is separate them from their mother while they're still suckling. Outdoor female cats with litters will often leave the kittens to go find food, and if someone stumbles along adorable kittens taking a nap, their first impulse could be to take them to the shelter or a foster home, Fried said.

"But if you see a kitten on the street and it's healthy, thriving and happy, it likely has a mama cat taking great care of it, and we need to focus foster homes on kittens who are sick, or injured, or truly orphaned," Fried said.

Kittens who are visibly dirty and look too skinny are more likely in need of help, Fried said, because those are signs they are orphaned.

Trap and release programs are a solution

Each year, over 3 million cats enter U.S. animal shelters, according to the ASPCA, and over 500,000 are euthanized.

Zweigart's nonprofit, Flatbush Cats, focuses on humanely trapping community cats in Brooklyn and spaying or neutering the animals to prevent them from adding to the stray population.

"We learned pretty quickly that we were not going to be able to rescue or adopt our way out of this problem," Zweigart said, referring to the importance of spaying and neutering outdoor cats.

The cat distribution system only works, Zweigart said, after you've investigated whether the cat already has an owner by posting to community forums, knocking on neighbors' doors and checking the cat for a microchip.

At that point, you don't need to thank the universe, Zweigart said.

"The people who end up adopting and rescuing a cat unexpectedly needed that companion more than they understood," Zweigart said. "You had to have already been in a place where you were ready for that animal, whether you understood it or not."