The bull market continued in 2017, with tech stocks outpacing the broader market. The tech-heavy NASDAQ had rallied nearly 30% this year as of this writing, compared to the S&P 500's 20% gain. There were some big winners in that market, but there were also huge losers that crushed investors. Let's take a look at the four worst-performing tech stocks of the year, and see where they might be headed in 2018.

A man in a suit watches a red chart line plunge through the floor.

Image source: Getty Images.

Frontier Communications

Regional telco Frontier Communications (OTC:FTR) lost 86% of its market value this year due to its shrinking customer base, declining average revenue per customer, high churn rates, and three straight quarters of net losses.

Frontier slashed its dividend by 60% in May, but the stock's subsequent decline inflated its forward yield to a whopping (and clearly unsustainable) 34%. Analysts expect Frontier's revenue to rise 2% to $9.1 billion this year, followed by a 5% decline next year. On the bottom line, Frontier is expected to post net losses for both 2017 and 2018.

Frontier's stock tumbled so quickly that it executed a 1-for-15 reverse stock split in July. If it hadn't done that, the stock would be well below $1 today. Frontier doesn't look like it can recover anytime soon.

Synchronoss Technologies

Synchronoss Technologies (NASDAQ:SNCR) provides various types of mobile software for enterprise customers, including personal cloud services, security tools, and messaging platforms. Those are high-growth markets, but Synchronoss' stock tumbled 76% this year on some serious concerns about its business.

Back in April, the company's CEO and CFO both abruptly resigned after warning that the first quarter would be an ugly one. The following month, Synchronoss delayed that quarterly report, and disclosed that it needed to restate its financial statements for both 2015 an 2016.

It started reviewing strategic alternatives for its business in July, which resulted in the sale of Intralinks, which it had just acquired at the beginning of the year. NASDAQ issued a delisting warning to Synchronoss in November due to its delayed financial filings over the past three quarters. With no way to properly value this company or trust its management, it's no wonder that investors have bailed out.

Windstream Holdings

Regional telco Windstream Holdings (NASDAQ:WINMQ) crashed 74% this year after posting a streak of dismal revenue growth and net losses. It reported some improvement in strategic enterprise sales and broadband subscribers last quarter, but that couldn't offset its widening losses and plummeting operating income, which fell 67% annually.

Income investors stuck around in the past for Windstream's dividend yield, which started the year at about 8%. Unfortunately, Windstream completely eliminated that dividend in August, along with its $90 million buyback program.

CEO Tony Thomas called the cash-conserving moves "the right path for our company," but investors still headed for the exits. Analysts currently expect Windstream's revenue to rise 9% this year, but drop 2% next year. On the bottom line, it's expected to post net losses over the next two years.

Pandora Media

Music streaming pioneer Pandora Media (NYSE:P) is being battered by headwinds on multiple fronts. Its user growth is slowing to a crawl, its ad revenues and premium subscription fees aren't generating enough revenue, content licensing costs continue rising, and massive competitors like Spotify and Apple Music are fragmenting the market.

A man lying on the couch, wearing headphones, and looking at an electronic device.

Image source: Getty Images.

Pandora's revenue is still rising, albeit at single-digit rates over the past three quarters, but it's posted seven straight quarters of net losses. Wall Street expects its revenue to stay nearly flat this year, but for its earnings to stay deep in the red.

There's no easy way out of this hole since tougher competition in the streaming music market will inevitably lead to price cuts for consumers and higher licensing costs from record labels. Bigger companies can afford to take losses to expand their user base, but Pandora can't. That's why the stock tumbled 64% this year.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.