What happened Shares of Harmonic (NASDAQ: HLIT) were tumbling this morning after the company reported its fourth-quarter and full-year 2021 results late yesterday. While Harmonic's revenue and earnings figures were better than expected, investors weren't happy that earnings fell on a year-over-year basis and that 2022 guidance is below Wall Street's expectations. The tech stock was down by 13.2% as of 11:45 a.m. ET. So what Harmonic, which designs, manufactures, and sells products and systems that enable network operators to deliver broadcast and on-demand video services, reported fourth-quarter non-GAAP (adjusted) earnings per share of $0.16, which beat analysts' consensus estimate of $0.13 per share for the quarter. Additionally, the company's total sales for the quarter of $155.8 million surpassed Wall Street's expectation of $149 million. Image source: Getty Images. Harmonic CEO Patrick Harshman said in a press release that the company "ended 2021 with exceptional quarterly results, including record revenue and bookings" and it's on "a strong foundation for sustained momentum as we enter 2022." But investors appeared to be disappointed that the company's non-GAAP earnings per share of $0.16 was below the $0.20 per share in the year-ago quarter. Additionally, investors may be focusing their attention on Harmonic's guidance for fiscal 2022. Management said earnings per share is in the range of $0.26 to $0.40, which means it could fall far below analysts' consensus estimate of $0.49 per share. Now what While Harmonic delivered fourth-quarter results that surpassed Wall Street's expectations, the fact that the company's non-GAAP earnings fell from the year-ago quarter worried some investors today. Investors may want to keep an eye on whether this is a temporary drop or part of a larger pattern for the company. In either case, selling a stock based on the results of one quarter typically isn't a good approach to long-term investing. 10 stocks we like better than HarmonicWhen our award-winning analyst team has 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.* They just revealed what they believe are the ten best stocks for investors to buy right now... and Harmonic 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 January 10, 2022 Chris Neiger has no position in any of the stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. The Motley Fool has a disclosure policy.Source