Warren Buffett was critical of a stock market that he said is increasingly driven by speculative trading, as opposed to investing for the long term.

“It’s tough to find values when everybody is preferring gambling,” Buffett told CNBC’s Becky Quick.

The chairman of Berkshire Hathaway had sharp words on the stock market earlier this year. In May, he likened it to “a church with a casino attached,” specifically calling out the surge in one-day options trading as “gambling.”

The stock market has rallied to all-time highs this year, climbing a wall of worry that included an energy shock from an ongoing war with Iran. Skeptics have said there’s too much speculation in stocks tied to the artificial intelligence build-out, with vehicles such as options and leveraged exchange-traded funds adding fuel to the fire. Equities have increasingly attracted retail traders en masse, who are buying shares of memory chipmaker Micron and recent initial public offering SpaceX.

The billionaire investor, 95, known for his stout adherence to value investing expressed his belief that the most meaningful investment opportunities are fewer and far between, requiring a patient and disciplined approach.

“There are times when opportunities are just thrown at you so fast you can’t, you know, it’s unbelievable,” the Berkshire chairman said. “And then there’s other times when you’re very, very lucky if you find one thing in a couple of years. And it should always be that the, the latter is what prevails.”

“But since humans love to gamble so much, there’s more money in, in actually cultivating gamblers than there are cultivating investors,” he said.