One of the country's leading industry groups has blasted the government's fresh round of workplace laws, describing the proposed changes as an "incoherent mess".
Australian Industry Group chief executive Innes Willox told a Senate inquiry the legislation was inconsistent and would hold back investment.
"The bill will not lead to the creation of a single job, it will stifle innovation. It will discourage employment and investment," he told the committee on Tuesday.
"When viewed in its totality, it remains a bad bill and an incoherent mess. Indeed, it would implement various measures that are simply unworkable."
The changes would prevent companies undercutting employees with labour hire and increase protections for gig workers.
But Mr Willox said the workplace laws would do nothing to address productivity or lift wages.
"It focuses entirely on imposing new complexities, inflexibilities and compliance burdens on employers," he said.
"It would override carefully considered approaches settled by the Fair Work Commission and High Court relating to fundamental concepts underpinning our system."
Earlier, the inquiry heard from care workers who warned online service platforms fuelled a race to the bottom, worsening employment conditions.
An anonymous carer who appeared before the inquiry said workers using online care platforms such as Mable were under pressure to constantly lower prices.
"Workers on Mable don't have much control over their work because they join the platform to start earning," the witness told the inquiry.
"I found that you'll give Mable an inch and they take a mile.
"I noticed the occupation health and safety standards for workers were not up to the standard and, unfortunately, not much has changed."
Another worker told the inquiry there was pressure to perform unpaid hours to be competitive on the service.
"I had to charge lower and lower because clients would negotiate my prices down because a majority of the clients were self-managed," they said.
Mable argued the workplace changes were not needed, saying more than half the working relationships on the platform were six months or longer, which should not be considered gig work.
Mable executive director Peter Scutt told the inquiry the platform supported minimum standards for workers.
"Our objective has been to ensure that people with disabilities, older persons and independent contractors can all continue to engage cost-effectively in a manner of their choosing, with the flexibility and safeguards they value," he said.
"Mable's future is intrinsically dependent on enabling good outcomes for all users on our platform."
Australian Services Union acting national secretary Emeline Gaske said loopholes needed to be closed in order to protect workers.
"We are seeing a race to the bottom in conditions in the workforce, which is only exacerbating the pace with which people are leaving the sector," she said.
"Unregulated platforms like Mable can exploit the loopholes that exist and can operate more profitably than traditional services because they keep a higher proportion of the NDIS funding and undercut other providers."
Disability service provider Hireup has thrown its support behind the proposed changes.
Executive director Jordan O'Reilly told the inquiry Hireup offered all of its workers formal contracts, saying the existing gig economy model was failing employees.
"Many (platform companies) have been perfectly aware of the big lie at the heart of the gig economy," he said.
"The lie has allowed companies to get away with misclassifying workers as independent contractors rather than employees."
The inquiry will hand down its findings in February.
