"It's about the X-factor," says the gregarious agent, who started Red Eleven six years ago with business partner Mandy Jacobsen. They now have 60 models on their books, including international star Grace Hollows, who cut her teeth with the likes of Kate Sylvester and Karen Walker, and has since worked in Tokyo, Paris, London and walked the runways at New York Fashion Week.
Being born pretty will only take you so far. Regardless of concerns by some about extreme skinniness being the norm, the reality is that those under 25 who make it to the fashion meccas of the world are typically size eights "or small size eights", says Betts. The ideal height for a professional clothes horse is 1.78m for girls, 1.88m for boys.
There are always exceptions - designers are increasingly using plus-sized models and Kate Moss is famously short in modelling terms at just 1.67m. But the typically tiny measurements suggest it's a far more likely - and healthy - career choice for the naturally slim.
Models must also have good bone structure, proportion and poise. Then there's personality, that magic ingredient that can transcend a 2D image and make it come alive. And cultivating a thick (yet glowing) skin to deal with the relentless scrutiny as well as the inevitable rejections that come with the job is crucial.
Focus and determination are even more important. There's a misconception that once a model is signed to an agency, the jobs start pouring in. Once signed, it's not uncommon for models to be asked to lose weight or tone up, or simply to finish school before they take on international jobs. Betts has just signed Bianca from New Zealand's Next Top Model, who is working on her fitness so she can model swimsuits.
Betts says the majority of girls (and boys) are young when they are first signed and are unprepared for the realities of their profession.
But for those who are prepared to make something of themselves, the opportunities are endless. Betts points to the world's highest-paid model and businesswoman Gisele as an example of how far modelling can take you - granted, the Brazilian has an extraordinary beauty, but it's her brain that has taken her to the top. Like anyone with a gift, it's up to the individual to develop it.
"We had a girl who was tall, beautiful, had style and personality and she was lazy. She didn't want it enough and was always pointing the finger as to why she wasn't getting work. If you get up really early like the rest of us and exercise really hard, you just might do well."
The smart models, who want to use modelling to get ahead financially or to see the world, are the ones who do best, Betts says. For those keen to model full-time, leaving New Zealand is a given, although that can come down to where they're at with their schooling or how comfortable parents are about their child jetting off around the world. Runway work accounts for the smallest part of the job, says Betts, but it's how you become a star and get the big campaigns.
"Most models don't go overseas until they're 17. Imogen Watt was 15. Her mum was amazing and strong. She got mum on board and went to Japan on a contract after school, which set her career up. Whereas this year is all about school - it's her NCEA year, so it's less about modelling."
Red Eleven has several models working around the world. Ariel Urlich is in Thailand on an American job, Caitlin Lomax is doing the Paris Fashion Week circuit, modelling for Louis Vuitton and Miu Miu, and Gina Morrissey is in Japan. Grace Hollows is in London, where Lili Sumner is about to head.
Having a good foundation in life, be it personal strength or education, is all the more important when you consider that the majority of models do their best work in their late teens and 20s.
But it is possible to model "for a really long time" says Betts, who points to the likes of occasionally grey-haired Kristen McMenamy, 46, Christy Turlington, 42, and Stella Tennant, 41, who continue to land big campaigns.
However glamorous and exciting the world of modelling appears, the downsides are plentiful too. There's the discomfort involved in shoots that might require the model to wear a woollen coat in the sun for hours, or a swimsuit in the snow. Models aren't always the top priority on a shoot either, says Betts.
"There's often a lot of resentment towards you as a model. Often they don't feed you properly on shoots: you're a model, you don't eat. Or they'll order you a pizza. Or they don't treat you properly: you're a model, stop complaining.
"You're punished for being beautiful. Some people resent the fact you're getting paid more than others."
She's heard plenty of horror stories, particularly when it comes to burns. A careless hair stylist burned a model's scalp and face at New Zealand Fashion Week; another model lost several jobs after sustaining burns lying on a piece of hot glass for a shoot.
Some girls simply find the pressure overwhelming or struggle with homesickness.
"It's a shame, because modelling can change girls' lives. It makes all the difference to them. These models have the capability of buying themselves a house by the time they're 25 if that's what they want. It's the kind of freedom ordinary people dream of."
