"One in three millennials will turn over in the first 90 days. The reasons for failing, 62 per cent is poor performance, 50 per cent is absence, 25 per cent is lateness and 30 per cent is gross misconduct."
Weiss said absence, lateness and misconduct were "clearly an own goal", while poor performance could be a result of the employee not knowing what was expected of them or overstating their abilities.
"The first three months of anybody's employment are fraught with risks on both sides," he said. "Often companies' recruitment processes are at fault, on the employee side it may be that they didn't understand what the company was wanting or have oversold themselves."
Younger people are also more likely to quit voluntarily. "Younger people will typically say, it's not as great as I want, not as exciting, you're underpaying, or frankly at the millennial end they're just lazy, and I mean that genuinely," he said.
While he didn't want to generalise and say "every millennial is like this", Weiss said "broadly it's an entitled generation" and "probably also over-informed as well". "People are constantly on their phones, constantly wired to hear where the grass is greener," he said.
"Every is looking at everybody else's highlight reel. People are not posting about how crap their current role is and what they're really going through, they're just living the high life. It gives an overinformed skew of the grass is always greener somewhere else."
Weiss said that was compounded by a lack of "resilience" as a result of being brought up "cotton-balled and molly-coddled". "At the first sign of difficulty, it's a choice of fight or flight, they typically choose flight," he said.
Finally, young people who find themselves out of their depth are often too embarrassed to speak up. In the book, Weiss tells the story of a girl named Tory, who got a job just out of uni in her early 20s.
"She realised her new line manager expected so many things out of her and she didn't have the confidence to admit she didn't know (how to do them)," he said. "She felt admitting she didn't know meant she wasn't supposed to be in that job, so she'd get fired."
Weiss said she would "sit in meetings like a stunned mullet". She was eventually offered options for training but she didn't want to be seen to be taking them for fear of being seen as incapable.
"She started to drown in stress and instead of just asking for help, she quit," he said.
According to Weiss, nine out of 10 companies do not offer new employees "structured onboarding" beyond basic orientation, but when they do the chance of staying on and being successful "increases by 69 per cent".
Structured onboarding would include a sit-down with the employee to go through each of their duties one by one and explain "what good performance looks like" within the first three months.
"If there are any realistic low-hanging fruit projects that can be delivered on, then the new employee and employer should agree on those as a test," he said. "Sadly the majority of companies throw people in the deep end and expect them to muddle through."
