The stock market had a mixed day on Wednesday, seeing substantial swings during the trading session that eventually led to gains for the Dow Jones Industrial Average but losses for the small-cap-focused Russell 2000 index. Investors seemed torn between an earnings season that has generally gone fairly well and the potential roadblocks to future economic growth both in the U.S. and globally. Bad news from some individual companies also weighed on sentiment. Capital One Financial (NYSE:COF), PTC Therapeutics (NASDAQ:PTCT), and Quotient Technology (NYSE:QUOT) were among the worst performers. Here's why they did so poorly.

Capital One falls short

Check out the latest Capital One Financial earnings call transcript.

Shares of Capital One Financial dropped 6% after the credit card banking company reported its fourth-quarter financial results. Net revenue for the bank rose 1% from the prior-year period, but larger provisions for credit losses and higher non-interest expense figures held Capital One back compared to its industry peers. As competition in the credit card industry has grown ever fiercer, Capital One has had to pay up in order to woo customers. That trend is a troubling one, and if it continues, then Capital One could see further headwinds during 2019.

Green credit card with Capital One Spark Business branding.

Image source: Capital One.

PTC Therapeutics sells some stock

Check out the latest PTC Therapeutics earnings call transcript.

PTC Therapeutics saw its shares drop 10% in the wake of its announcement of how its secondary stock offering priced in the market. The company had said late Tuesday that it would sell $200 million in shares, and Wednesday morning, PTC said that the price of the offering would be $30.20 per share, resulting in 6.72 million shares being sold. Given that it had closed above $33 per share Tuesday afternoon, that came as a shock, and the stock traded below the offering price for most of the trading session. Moreover, with the stock having been in a downturn since mid-2018, the timing of the stock offering was particularly unfortunate.

Quotient sees tough times ahead

Check out the latest Quotient Technology earnings call transcript.

Finally, shares of Quotient Technology closed lower by 8.5%. The digital promotion specialist warned that its fourth-quarter revenue figures would be substantially weaker than it had originally expected, blaming customers who chose to reduce their promotional spending during the key month of December. Quotient also believes it will now lose more money than it thought as a result of the revenue hit. It's too early to tell whether the impact will ripple forward into 2019, but investors will have to watch closely to see whether Quotient's clients go back to spending on promotional activity in the future.

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