Risk-averse investors flock to dividend stocks, hoping that the steady trickle of payouts will provide income as well as downside protection. But everyone knows that there's no such thing as a perfectly safe stock. Volatility is just a part of the game, and sometimes even a sustainable dividend isn't enough of a safety net.

Income investors who bought into Camping World Holdings (NYSE:CWH), Universal Display (NASDAQ:OLED), and Arcos Dorados (NYSE:ARCO) expecting reasonable capital appreciation and supplemental income have only received the latter in recent months. The three stocks have shed nearly a third to almost half their value this year, more than wiping away the modest distributions. Let's go over what tripped up Camping World, Universal Display, and Arcos Dorados in 2018. 

Exterior of a Camping World superstore in Bowling Green.

Image source: Camping World Holdings.

Camping World: Down 49%

Helmed by CNBC's The Profit star Marcus Lemonis as its CEO, Camping World went public at $22 in late 2016, more than doubling by the end of last year. The leading RV retailer was attracting plenty of bullish attention as it made the most of a highly fragmented sector by snapping up independent dealers. 

Its decision in January to acquire outdoors retailer Gander Mountain raised some red flags. Was Camping World losing its focus on RVs by aiming for grander outdoor lifestyle retailing? It also moved to switch out its auditor, something that is never a good look.

However, the biggest drag on Camping World is that the RV market itself is going through some hiccups. Average selling prices on vehicles are sliding, and shares of RV makers Winnebago (NYSE:WGO) and Thor Industries (NYSE:THO) have shed 24% and 34% of their value, respectively, this year. Paying out modest yet consistent dividends didn't help. Camping World, Winnebago, and Thor pack yields of 1.4%, 1%, and 1.6%, respectively, after the sell-offs. 

Universal Display: Down 44%

Another dividend payer that is following up a great 2017 with a horrendous 2018 is Universal Display. The patent-rich champion of organic light-emitting diode (OLED) technology was a rising star last year when the battery-efficient screen tech finally cracked the iPhone market. However, as iPhone X sales languished and OLED use in TVs and tablets failed to move the needle (revenue declined 22% in the first quarter), Universal Display came under fire.

Universal Display argues that OLED has emerged to take 10% of the display market in consumer electronics over the past decade, but it remains to be seen where it goes from here. Universal Display's yield of 0.3% is the lowest among the stocks singled out in this article, but it's yet another income producer that has been painful to own this year. 

Arcos Dorados: Down 32%

Investors in Arcos Dorados haven't been singing the McDonald's (NYSE:MCD) "I'm lovin' it" jingle lately. Shares of the world's largest independent McDonald's franchisee -- and Latin America's largest restaurant operator -- have surrendered nearly a third of their value this year. 

Arcos Dorados is holding up well in terms of growth. But after the stock nearly doubled last year, investors entered 2018 with high expectations that have yet to be fully realized. Arcos Dorados' franchised McDonald's locations are growing sales nicely through Latin America, but it did fall short of Wall Street's earnings expectations in its most recent quarter. Nearly half of its 2,190 locations are in Brazil, so the wild currency swings will add to the company's performance volatility.