What happened

Growth-focused tech investors are having a tough start to the short trading week. In afternoon trading on Monday, shares of HubSpot (NYSE:HUBS), Appian (NASDAQ:APPN), and Zendesk (NYSE:ZEN) were down as much as 15%, 11%, and 11%, respectively.

So what

Double-digit moves are normally accompanied by newsworthy items, but that doesn't appear to be the case today. HubSpot, Appian, and Zendesk didn't issue a single press release today. They weren't on the receiving end of an analyst downgrade either. Instead, the common thread that links all three of these companies -- they all operate using a software-as-a-service (SaaS) business model -- appears to be the primary reason for today's decline.

Multiple SaaS companies took a beating on Monday for no apparent reason. While the pain was felt by scores of stocks, HubSpot, Appian, and Zendesk appear to be getting hit harder than most. That makes some sense, given that all three companies are growing like crazy and trade at high valuations.

Businessman being punched in the face with a boxing glove

Image source: Getty Images.

For evidence of the beatdown, consider that the First Trust Cloud Computing ETF (NASDAQ:SKYY) -- an ETF that owns 29 companies involved in the cloud computing industry -- declined by more than 3.5% in afternoon trading on Monday. That's a huge move, considering that the fund's assets are largely focused in big-cap names like Oracle, Alphabet, and Cisco Systems.

Now what

Lots of SaaS companies have been on a tear over the last few years, so it's understandable that they're now taking a breather. Even after today's drubbing, the First Trust Cloud Computing ETF is up 144% since its debut in 2011. That's why the key question for investors to ask themselves is whether they still believe in each company's future.

HubSpot -- a leader in the shift toward inbound marketing -- just reported expectation-topping sales growth of 35% and cranked out an impressive non-GAAP (generally accepted accounting principles) net income of $0.17 per share. Margins also rose across the board, and the company's total customer base expanded by 40% over the year-ago period. Those look like healthy numbers to me.

It was a similar story at Appian. The pioneer of low-code software posted total sales growth of 23% and non-GAAP earnings per share that exceeded guidance. The company also called for growth to accelerate into the upcoming quarter, and raised guidance for the full year.

Customer service specialist Zendesk reported the fastest growth rate of the group after posting a sales jump of 37% in its most recent quarter. Its non-GAAP EPS also swung from a loss to a profit, and its dollar-based net expansion rate remained strong at 118%. Those numbers suggest that this business is still firing on all cylinders, too.

Given the lack of new information and strong earnings reports by all three companies, investors can likely chalk up today's drubbing to just plain old market noise. Big moves like this are not fun, but they come with the territory when investing in high-growth stocks that enjoy lofty valuations.

If you were bullish on any of these businesses yesterday, then I see no reason to change your tune today.

Suzanne Frey, an executive at Alphabet, is a member of The Motley Fool's board of directors. Brian Feroldi owns shares of GOOGL, GOOG, Appian, and HubSpot and has the following options: long January 2020 $38 calls on ORCL and short January 2020 $38 puts on ORCL.

The Motley Fool owns shares of and recommends GOOGL, GOOG, Appian, HubSpot, and Zendesk. The Motley Fool owns shares of ORCL and has the following options: short December 2018 $52 calls on ORCL and long January 2020 $30 calls on ORCL. The Motley Fool has a disclosure policy.