IRobot's CEO told "Fast Money" Wednesday that he's sticking by his full year guidance for the defense part of his business—even though it was the weak spot in its first quarter.

This comes a day after the Roomba maker's earnings beat Wall Street estimates. But, the results showed profits were down year-over-year. Guidance for next quarter also came in light.

The stock closed down more than 10 percent at $35.52.

"Defense is a small part of our business, and so that our exposure to the defense industry is relatively modest. We had a great first quarter on the home robot side, up 17 percent. Obviously that was pulled down a little bit by a weak quarter on the defense side," said Colin Angle, iRobot chairman and CEO.

Angle also addressed iRobot's goal to pick up a larger share of the vacuum market.

"I don't understand why people still want to push vacuums. The state of technology for robotic cleaning has gotten to the point where you can routinely clean every single day with your robot and get results similar to upright vacuuming," said Angle, "It's just a better way of doing things and we're just getting started."

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