Why aren't there more female venture capitalists? Because there are just too few quality women.

At least that's the message that Michael Moritz, chairman at Sequoia Capital, sent during a recent interview.

Sequoia is one of Silicon Valley's most prolific venture capital firms, investing in companies like Google (GOOG), Instagram, Airbnb and Dropbox. It also has zero female investing partners in the U.S. -- meaning women who make decisions about investments. That's a stat that Moritz said the firm thinks about "a lot."

Moritz, a former journalist, said that Sequoia looks "very hard" for female partners to join the fund.

"I like to think, and genuinely believe, that we're blind to somebody's sex, to their religion, to their background," he said during an interview with Bloomberg's Emily Chang.

But Moritz said the firm is "not prepared to lower our standards" to get more women in the door.

He said Sequoia is looking for people who are ambitious, hardworking and have tech backgrounds -- and it's had trouble finding women with all those qualities.

"If there are fabulously bright women who are really interested in technology, very hungry to succeed and can meet our performance standards, we'll hire them all day and night," he told Chang.

(The irony wasn't lost on investor Bryce Roberts, who tweeted that Moritz himself studied history.)

What does Moritz think is to blame? He cited the commonly referenced "pipeline" problem.

"I think the issue begins in the high schools. Women tend to elect not to study the sciences when they're 11 and 12," he said. "Suddenly, the hiring pool is much smaller."

Diversity consultant Joelle Emerson says the belief that companies must lower standards in order to hire women is misguided.

"[It] is one of the biggest barriers to successfully cultivating a more diverse, inclusive industry," she said. "Beyond being obviously offensive to imply that hiring women requires a lowering of standards, it's totally incorrect."

Emerson's firm Paradigm advises and trains tech companies and VC firms on how to boost diversity. She said recruiting methods are likely to blame.

"All too often [companies] use hiring practices that are ad hoc, subjective, and, as a result, deeply influenced by bias," she said, adding that companies need to focus on recruiting from a wider pool of candidates.

That helps ensure that companies aren't just pulling from the networks closest to them -- which tend to be made up of people who look and think like them.

Moritz dialed back his comments on Thursday.

"I know there are many remarkable women who would flourish in the venture business," he said in an email statement sent to CNNMoney. "We're working hard to find them and would be ecstatic if more joined Sequoia or other firms."

Sequoia does have female investors in its China and India offices.

The lack of female investors at top investment funds isn't abnormal. A recent study found that 92% of senior investment teams at top VCs are male, which is even worse than that of major tech firms, where 77% of leadership teams are male.