Though it is still unclear what led Birgfeld to allegedly run Models Inc., one possible -- maybe obvious -- explanation for behavior like Birgfeld's is money.
"Generally the primary motive is money," said ABC News consultant Dr. Michael Welner, a forensic psychiatrist and the head of the Forensic Panel, adding that the escort business would allow someone in Birgfeld's position to quickly make a lot of money without any advanced education or training.
"Without interviewing her, my only frame of reference is what comes up time and again," he said. "And time and again the money is fantastic and you can't beat it."
Police say Birgfeld worked several jobs. In addition to the escort agency, she ran a chef's consulting business, taught dance to preschoolers and sold baby products.
The Grand Junction Sentinel reported that investigators have also visited a downtown office kept by Birgfeld, where they found a massage table and what appeared to be acupuncture equipment. Police would not confirm or deny the report
Joel Dvoskin, a forensic psychologist and the president of the American Psychology-Law Society, agreed with Welner's assesment.
"Logically, it's more likely that there's a financial cause," he said, adding that it would be too difficult to speculate on the myriad possible psychological reasons that Birgfeld might work at an escort service, given how little is known about her. "Money is often why people do things."
Some people who have engaged in similar illicit behavior have been driven by psychological disorders and a desire to add excitement to their lives, experts said.
"More often than not, part of it is the thrill, adding excitement to an otherwise 'boring' life," said McCrary. "They want to have a dark secret, to walk on the wild side a little bit."
Working in the sex trade in particular can offer an allure of danger. "They acquire an aura of being sexy, which you don't necessarily retain after marriage and motherhood," said Ramsland.
Welner, though, disputed that characterization, saying that the sex workers he has treated are not attracted to the danger of the work.
What little is known about Birgfeld also appears consistent with some personality disorders, said Dr. Elliot Atkins, a forensic psychologist. Atkins suggested that working several different jobs while raising three children could be consistent with a need for approval and affirmation or with the manic activity associated with bipolar disorder.
People with bipolar disorder are often easily bored and are stimulated by stress of balancing different parts of their lives. They often engage in several projects at once and often engage in sexual indiscretions, he said.
"In this case, one of the things we see is that she appears to be somebody who's very busy, engaged in multiple activities and multiple relationships," he said. "What we see is an individual who has an extremely high level of energy, or need for excitement."
All of Birgfeld's different activities are consistent with the "grandiose thinking of someone in a manic state," Atkins said.
The stresses of leading a hidden life often leads people to unravel and may lead to anxiety, depression and other mental illness.
"Sometimes they react with violence, sometime they will just slip away and start over somewhere," said Ramsland.
"If you have any conscience at all, you do begin to feel the guilt," she said.