What could possibly go wrong for a start-up after raising $6.9 billion in their first eight years? Quite a lot apparently, according to a growing number of experts commenting on entrepreneur focused office-space-rental company WeWork, the seventh most valuable private-market start-up in the world. The level of investment itself is, of course, proof that others have strong belief in the firm’s potential for success.

In August 2017, we reported on the $4.4 billion investment made by Japan’s SoftBank Group and the SoftBank Vision Fund, the brainchild of Masayoshi Son, an unusually risk-loving Japanese telecoms and Internet entrepreneur. As CEO of SoftBank, Son has been responsible for a variety of seemingly risky investments that have paid off to make the Vision Fund the world’s biggest growth fund by some distance at $100 billion. In fact, the next biggest private equity growth fund reaches just over $20 billion, whilst the next three biggest growth funds of venture capital firms add up to a mere $12bn combined.

The most famous of Son’s successes was the $20 million dollar investment made into a young marketplace platform called Alibaba. When the Chinese firm went public in 2014 it became the world’s biggest IPO, and SoftBank’s 28% stake in the firm is now worth $140bn. Earlier investments in Yahoo and more recent investments in chip-maker ARM and ride-sharing firms such as Uber have also been considered as strong successes.

Son is an enigmatic man, a person close to him claims that he seldom sees anything but upside. While Mike Cagney, co-founder of SoFi, a US fintech firm in which Mr Son has invested said of Son, “If he came in and levitated one day I would not be surprised.” He invests in less than 5% of the start-ups that seek funding but for those he likes he has been known to interrupt an entrepreneur mid-pitch and say, “stop, I know. I’ve heard enough, how much do you want?” He then regularly offers up to four or five times more than the entrepreneur requests.

However, as the not-so-old Silicon valley saying goes, “start-ups perish more often from indigestion than starvation.” The major criticism thrown at Son and SoftBank’s strategy is that filling a start-ups coffers with more money than they know what to do with only leads to unrealistic expectations, thereby encouraging wastefulness, indiscipline and sloppiness.

In response, Son suggests that masses of capital ensures that founders can focus on the development of their businesses rather than preparing for and worrying over their next funding round. “Too much money has a bad effect,” he says, “but turbocharging the firms that have a great formula stimulates founders’ thinking and gives them stamina.”

It can’t all be success however and question marks have been raised over the large investment and subsequent valuation in WeWork. “Putting $4.4bn into WeWork, a provider of shared workspaces, valuing it at $20bn, is another risky bet [from Son]. The firm leases office space, redesigns it to create a hip vibe and sublets it to startups, freelancers and some big firms. The worry is that WeWork is little more than a commercial-property company that is unjustifiably trading on a tech valuation and will soon be rumbled,” stated a recent article in The Economist.

On the surface WeWork appear to be doing well so far, reportedly filling 81% of its deskspace, 21% over the 60% needed to cover its overhead-cost obligations. It has already set up co-working sites in 24 countries and has plans for further expansion, especially in the Asia-Pacific region, a prerequisite of SoftBank investments. It has acquired or started a number of new ventures including “co-living” space WeLive, a wellness club, a coding academy, and an alternative education elementary school as part of their WeGrow arm, led by Rebekah Neumann the wife of WeWork chief Adam Neumann.

They are also pioneering a number of innovative developments such as the AI Desk, which recognises individuals based on their smartphone and adjusts the workspace according to their preferences. “it's about customising spaces to suit our members, whilst recognising that different people can come in and out of the space on a regular basis," says WeWork European Transactions Director Mary Finnigan.

A closer look however, and a few substantial cracks start to appear. Bloomberg reports that WeWork’s had net losses of $934 million in 2017, and suggested that the company currently owes $18 billion in rent. While WeWork’s general and administrative costs rose almost threefold in 2017, primarily because it used Softbank’s investment to buy back stock from employees and early investors in October.

Despite the $6.9 billion dollars investment raised so far, WeWork appears set to seek more funding through a $500 million bond sale, the first debt financing for the company. Considering the money spent on somewhat-risky acquisitions, outstanding rent payments and net-loses, there are also fears that bringing in debt investors at this stage would put the firm in a financially precarious position. If, say, the tech bubble were to burst, WeWork might might find themselves in free fall.

This, so far, is all hearsay however. Loss and debt are part of business for a fast growing start-up. The market for new age co-working spaces is healthy and growing, more importantly WeWork sits atop it comfortably. Rapid international expansion and their ventures into other markets spreads risk. Just because WeWork have yet to weather a real storm, or survive a burst bubble, does not mean they couldn’t. While the support and backing of Masayoshi Son with SoftBank offers a sure-footing and tactical savvy that makes failure hard to predict.

“[WeWork] is a really intriguing business model that is not yet mature,” said one commentator in an article for the Financial Times. “It may be the late innings of an economic cycle and it is really important to understand how this business model works when the economy weakens. It’s not clear to us how durable it is.” What is more clear is that if the start-up boom continues around the world, WeWork is likely to thrive as the king of flexible workspace.