In this era of Facebook, Twitter, the selfie and Embarrassing Bodies (a show about people too shy to go to the doctor about their problems but happy to reveal all to millions of TV viewers), we have become used to the compulsion to be famous, even if it's for Andy Warhol's allotted 15 minutes.
So it is strange to encounter an artist who was genuinely talented - New York Times critic Michael Kimmelman would later call her "one of the great American mid-century street photographers" - yet so uninterested in being famous she did not show anyone her work. At the time of her death many of her films remained undeveloped and the bulk of her negatives unprinted.
If it wasn't for the curiosity of John Maloof we might never have learnt anything about Vivian Maier, whose remarkable life - or, perhaps more accurately, unremarkable life - is the subject of one of the most fascinating documentaries at this year's Revelation Perth International Film Festival, which kicks off next week.
In 2007 Maloof was working on a book about his neighbourhood in Chicago. He needed photographs to illustrate the book so he went to a local junk and furniture auction house and bought for $US380 a box of negatives that had come from a storage locker that had been sold off when the owner could no longer pay the fees.
The photographs didn't make it into Maloof's book and he put them aside. Some time later Maloof again looked at his purchase and suspected he was in possession of something significant.
He scanned 200 negatives and uploaded them to a photo blog. The post went "insane", recalls Maloof, so he went on a mission to piece together the rest of Maier's work, buying more boxes that had been bought by others in a similarly offhand manner.
Thus began Maloof's quest to sort through, archive and release Maier's vast photograph collection - he acquired 100,000-150,000 negatives, 700 rolls of colour film and 2000 rolls of black-and-white film - and find out who Maier, who had died at 83 in 2009, was.
One of those who was struck by Maier's work, strikingly composed portraits of ordinary people and studies of mid-century American life that possess (according to The New York Times) "the immediacy of Weegee and the candour of Diane Arbus", was comedian Jeff Garlin of Curb Your Enthusiasm fame.
Maier used a medium-format Rolleiflex camera which allowed her to shoot at waist level so she could snap away without being noticed (it has been suggested her standard dress of oversized coats and broad hats were calculated to conceal, like a secret agent in a film noir).
"I was watching a piece on Vivian on a local CBS channel in LA," recalls Garlin, a Chicago native and photography buff. "And when I saw her stuff I was like one of those cartoon characters with my eyes popping out."
Garlin contacted Maloof and put him in touch with filmmaker Charlie Siskel (nephew of the late Gene Siskel of Siskel and Ebert fame) and the pair set about documenting Maloof's quest to discover the identity of Maier (Garlin took a producing role).
Maloof discovered Maier spent most of her life as a nanny working for well-heeled families in New York and Chicago, where she would live until her death, and spent almost every spare moment taking photographs, interspersed with shooting film and making audio recordings (she was a constant archivist of life unfolding around her).
Maier, however, was no Mary Poppins. Rather she was a stubborn, eccentric monomaniac who intrigued and annoyed the families who put up with her over the decades, many of whom are interviewed in the documentary (one woman is still clearly traumatised by the experience of Maier's mercurial, occasionally cold and cruel nannying).
One employer recalls how Maier collected so many newspapers that the floor in the upstairs quarters she occupied buckled under the weight. Another man remembers how his brother was knocked over by a car and, instead of coming to his aid, Maier recorded the whole horrific event with her camera.
While Maloof managed to track down many of her former employers, including famous talk-show host Phil Donahue, discovering identity proves a greater challenge because her family records are so sketchy (she had a French accent but nobody can work out why because she was born in New York).
Indeed, the deeper Maloof digs the more complex a personality emerges, so much so that today she probably would have been diagnosed as autistic (she had no love life, no personal relationships and, says one interviewee, was afraid of being touched).
We also learn through Maloof's extensive interviews with her employers and the now-grown children she cared for that she had an obsession with darkness and perversion in the dark side of American life, so much so that one of her charges believes that at one time Maier was molested.
While Maloof and Siskel are thorough in their determination to prove Maier a great outsider artist - interviewee Mary Ellen Mark compares her work with that of Helen Levitt, Robert Frank, Lisette Model and Diane Arbus - and talk to many people who knew her intimately they never solve the mystery of why Maier kept taking photographs but showed them to nobody.
"We all choose what we want the world to know about us. And yet in the end we can't help but reveal ourselves. It may be that if Vivian Maier had her choice the world would know nothing of her life or her photographs," Siskel says.
"But hiding one's art is, of course, the opposite of destroying it. Maier preserved her work and left its fate to others. Like Kafka's instructions to burn his writings unread, any wish she may have had for her work to remain unseen, either expressed or unspoken, was ignored."