Twitter Co-Founder Ev Williams Not Impressed by Wall Street. Not at All.

But how do you really feel, Ev?

Medium CEO and Twitter co-founder Ev Williams took a jab at Wall Street Wednesday, criticizing investors who have spent the last year and a half focused on Twitter’s monthly active user metric, or essentially how many people log in to the service every month.

Williams has argued this number is not necessarily the most important way to measure Twitter’s size. (We agree!)

“Wall Street does not have a sophisticated understanding of what creates value in this world,” Williams told Re/code Co-Executive Editor Kara Swisher onstage, as part of the Code/Media conference in Laguna Niguel, Calif. “Hopefully, that will improve over time. That’s a conversation I’m trying to start.”

The MAU metric is an important one for Twitter, and is used by Wall Street to determine the company’s general growth. Twitter has grown slowly, and added just four million new MAUs last quarter, despite an impressive financial showing. Coincidentally, you don’t see Facebook, which doesn’t seem to have a problem with growth, complain about this metric.

Williams, who still sits on the board at Twitter, has been outspoken about this particular metric before. When Instagram reached 300 million users in December, it passed Twitter in total size, but Williams wasn’t impressed.

“Saying Instagram’s bigger, or they have more people sharing pictures, that’s irrelevant,” he said. “You might as well say more people watch TV. I’m not trivializing TV, I’m just saying it’s not relevant to how many people are using Twitter.”

The crux of the argument, says Williams, is that Twitter provides immense value in other ways, like surfacing news and giving everyone a voice. Comparing Twitter to Instagram, where the use cases are completely different, doesn’t make sense.

So, what is the most important metric for Twitter? Ev didn’t say.

This article originally appeared on Recode.net.