Microsoft (MSFT -0.13%) is the worst performer on the Dow Jones Industrial Average (^DJI 0.81%) today. The stock was down 3% in afternoon trading, ahead of second-weakest trader Visa (V 0.12%), which was 2.9% lower. The Dow itself is doing fairly well, losing only 0.5% despite these two big drops dragging the index down.

But at least Visa has a reason to perform poorly today. The Labor Department this morning released a fresh jobs report that was a little bit weaker than expected. With fewer gainfully employed Americans than investors and analyst had hoped for, it's natural to assume that credit card processors will lose out on some expected business. Fellow credit card maven MasterCard (MA -0.09%) fell 2.8%, underscoring the sector-specific weakness.

But Microsoft doesn't have any particularly damning news to weigh on its stock today. It looks like another one of those frustrating random walks down Wall Street.

You could argue that the tech sector as a whole is plunging. According to Google Finance, tech stocks overall are down 2.1% today. But again, this is a black box with no obvious inputs.

No earnings reports, no notable analyst notes with industry-wide implications, no independent tech market research data showing worrisome numbers. And it's not even a big day for options expirations -- the third Friday of April is still two weeks away.

Nothing.

And yet, nine of the 10 largest tech stocks were trading in the red as of 1 p.m. EDT. And here's our first clue: The most consumer-friendly names on this list are the ones suffering the most.

Consumer-facing tech stocks, including Microsoft, are down by several percent. Those that mainly serve business-to-business interests hovered just below the breakeven line.

And here's another clue: Today's big tech losers have generally performed very well in recent months. Microsoft, for one, set 52-week record highs on three occasions in the past week.

MSFT Chart

MSFT data by YCharts.

That's because new CEO Satya Nadella has started to come across as a serious whiff of fresh air in Microsoft's stale business culture, shaking up exactly the right things.

Put these two clues together, and mix in a hint of Visa's woes, and you might come to this conclusion: The market's largest tech stocks are getting a quick correction as profit-takers see potential consumer weakness on the horizon. So why not snatch some solid profits off the table while the getting is good?

That's my thesis for today's strange market action, including Microsoft's sizable plunge. An educated guess is often the best an investor can do when it comes to explaining short-term market moves. If nothing else, Microsoft's weakness today serves as a useful reminder about taking the long view. It's usually safe to ignore daily ticker jumps, even if they're fairly large.