SAN FRANCISCO — Snap went public in March in what was one of the tech industry’s most highly anticipated initial public offerings of the year. Then the messaging and media company promptly posted dismal financial results for two consecutive quarters, piercing the hype.

On Tuesday, Snap continued to disappoint with its latest financial snapshot. The company reported revenue for the third quarter that missed Wall Street expectations and also posted a larger-than-expected loss, as well as high costs. In the aftermath, its stock plunged about 20 percent in after-hours trading but recovered slightly.

The numbers add up to a big question mark for Snap. While the Venice, Calif.-based company has been regarded as innovative in social media, it faces a juggernaut in its chief rival, Facebook. Over the past year, Facebook has copied some of Snapchat’s most popular features in an effort to peel away its users. That has hurt the growth of Snap’s user base and advertising revenue, and its stock has performed disappointingly, trading below its offering price of $17 a share for months.

“User growth is slowing; revenue growth is failing to live up to expectations,” said Rich Greenfield, a managing director at the research firm BTIG.