What: Shares of iRobot Corporation (IRBT -0.14%) fell more than 10% early Thursday after the home robotics company released strong fourth-quarter 2015 results but followed with lighter-than-expected forward guidance. 

So what: Quarterly revenue grew 29.6% year over year to $206.4 million, driven primarily by a 46% increase in domestic home robot sales to $84.3 million and a 19% increase in international home robot sales to $90.9 million. Meanwhile, net income more than doubled over the same period to $19.3 million, or $0.65 per share.

By comparison, iRobot's guidance called for revenue of $200 million to $205 million and earnings per share of $0.53 to $0.58. Analysts, on average, were anticipating earnings of $0.56 per share on revenue of $202.3 million.

"Our Roomba marketing programs were highly successful in the United States," explained CEO Colin Angle, "where Q4 sell through at our top 5 retailers was up more than 70% year-on-year, resulting in a significant return on our investment. We are highly confident that we have the right marketing mix to export overseas to accelerate growth in those markets, and we expect revenue in all three geographic regions to grow in the low to mid-teens in 2016."

Now what: For the current quarter, however, iRobot anticipates revenue of $125 million to $135 million -- or growth of 6% to 14.4% over the same year-ago period -- which should translate to a range of a net loss of $0.03 per share to net income of $0.04 per share. Analysts' consensus estimates called for revenue of $137.9 million and earnings of $0.25 per share.

However, keep in mind that iRobot's bottom-line guidance includes roughly $0.05 per share in one-time divestiture costs related to its previously announced sale of its defense and security business to Arlington Capital Partners and a per-share loss of $0.05 to $0.07 related to a stub period of one quarter of defense and security results. When iRobot initially announced this deal last week, Angle noted it will "maximize shareholder value by allowing [iRobot] to focus on [its] much larger Home segment."

Finally, for the full-year 2016, iRobot expects revenue of $630 million to $642 million and earnings per share of $1.20 to $1.40. Average analyst earnings were for $1.64 per share on revenue of $692.9 million, though. 

In the end, it's no surprise to see iRobot stock trading lower today following its guidance shortfall. But given its history of overpromising and underdelivering, as well as the one-time costs that primarily led to that shortfall, I can't help but think this is a knee-jerk reaction from the market to otherwise solid results.