What happened

Shares of eBay Inc. (EBAY 1.33%) were down 9.1% as of 2:45 p.m. EDT Thursday after the online marketplace announced mixed quarterly results and reduced its full-year revenue guidance.

More specifically on the former, eBay's second-quarter revenue climbed 9.1% year over year to $2.64 billion, or near the low end of last quarter's guidance for a range of $2.64 billion to $2.68 billion. On the bottom line, that translated to adjusted earnings of $533 million, or $0.53 per share, up from $0.45 per share in last year's second quarter and above eBay's outlook for a range of $0.50 to $0.52.

eBay office building at sunset.

Image source: eBay.

So what

The underlying drivers of eBay's results were mostly positive. Active buyers across its platforms grew 4% to 175 million. And gross merchandise volume increased 10% (7% at constant currency) to $23.6 billion, translating to 9.4% growth (or 6% at constant currency) in Marketplace revenue to $1.837 billion. Classifieds platform revenue also climbed 18% to $259 million. But sales at StubHub rose a more modest 4% to $246 million.

CEO Devin Wenig noted that the company has continued executing its strategy, both improving the eBay experience and pursuing opportunities in the advertising and payments spaces.

Now what

For the full year, however, eBay also reduced its outlook for 2018 revenue to be in the range of $10.75 billion to $10.85 billion, from its previous range of $10.9 billion to $11.1 billion. eBay also modestly increased its expected 2018 earnings range to $2.28 per share to $2.32 per share, up from $2.25 to $2.30 previously.

Management subsequently explained that with nearly 60% of eBay's business generated from international markets, this new outlook accounts for the negative effects on revenue of the strengthening U.S. dollar. It also assumes there won't be improvements in StubHub's market in the second half of the year.

In the end, that was more than enough to make investors doubt whether eBay stock is the best place to put their money to work, and shares are responding in kind.