Tech billionaire Tom Siebel rings the alarm on inflation, markets, and a potential recession. Here are his 6 best quotes from a new interview.

• Tom Siebel warned investors are facing a dangerous combination of market headwinds.
• The C3.ai boss drew parallels to the months before the dot-com crash and financial crisis.

Tom Siebel warned volatile markets are here to stay, underscored the inflation threat, and emphasized investors are facing a slew of challenges during Robert W Baird's consumer, technology, and services conference this week.

Siebel is the billionaire founder and CEO of C3.ai, a development platform for AI-powered enterprise applications. He warned the current hiring slowdown among Big Tech companies reminded him of the months before the dot-com bust and the global financial crisis, according to a transcript on Sentieo, a financial-research site.

The early Oracle executive also suggested the recent slump in technology stocks and cryptocurrencies might force crypto workers to get conventional jobs.

Here are Siebel's 6 best quotes, lightly edited for length and clarity:

1. "The next couple of years could be a little rocky in the markets. This is the perfect storm."

2. "The Four Horsemen of the Apocalypse all happened at the same time. Pestilence, famine, war, and death, we got them all." (Siebel pointed to the pandemic, Russia's invasion of Ukraine, and potential recessions in the US and Europe.)

3. "The idea of inflation at 8%, that's laughable. How do you have fuel prices go up 100%, groceries go up 22%, and rent go up 30%, and get 8% out of that?"

4. "I'm not an investor, I just like to build software companies. But it looks to me like this market expansion was about 70 years too long. And so I think this looks like a zinger."

5. "This could get ugly. What's the sequence? You saw this in 1980, you saw it in 2000, you saw it in 2008. The markets get all nervous and twitchy, you get all this volatility. Then people start announcing hiring freezes, then people start announcing layoffs. Facebook, Amazon, Salesforce, Tesla. What happens next?" (Siebel was suggesting an economic downturn and potential recession are looming.)

6. "All these people went home to work in their PJs and get paid in bitcoin. Their stock is worth 10% of what it used to be, okay? The rent has gone up 30%. The groceries have gone up 25%. They're saying, 'Oh dear, I need to go get a job.' Things are going to change."

Read more: Stocks haven't looked this cheap since the start of the pandemic, according to Morningstar's chief market strategist. He shares 8 undervalued names to buy - and 4 headwinds that investors should still be worried about.