What happened Shares of Roku (NASDAQ: ROKU) fell 17.6% in March 2021, according to data from S&P Global Market Intelligence. The media-streaming technology expert didn't actually do anything to deserve a dramatic haircut, but the stock was swept up in a couple of market-moving events beyond Roku's control. So what Roku entered the month of March on a full head of steam. The company absolutely smashed Wall Street's expectations in February's fourth-quarter report. Share prices had increased by 248% in 52 weeks. The massive gains set Roku up for a sharp correction when the market tenor turned away from high-growth stocks that had posted large gains during the coronavirus era in favor of low-risk value investments. In particular, Roku was and is a large investment in money manager Cathie Wood's popular ARK Innovation ETF (NYSEMKT: ARKK) whose constituents were singled out as specific targets in this growth-stock drop. Image source: Getty Images. Now what As an unprofitable company with a $46 billion market cap and sky-high valuation ratios, Roku is vulnerable to this type of broad market retreat from risky growth stocks. It may not be your cup of tea, but I'm sorely tempted to add to my own Roku holdings on volatility-based dips like this one. 10 stocks we like better than RokuWhen investing geniuses David and Tom Gardner have a stock tip, it can pay to listen. After all, the newsletter they have run for over a decade, Motley Fool Stock Advisor, has tripled the market.* David and Tom just revealed what they believe are the ten best stocks for investors to buy right now... and Roku wasn't one of them! That's right -- they think these 10 stocks are even better buys. See the 10 stocks *Stock Advisor returns as of February 24, 2021 Anders Bylund owns shares of Roku. The Motley Fool owns shares of and recommends Roku. The Motley Fool has a disclosure policy.Source