Amazon's hardware boss explains why the Fire Phone flopped but the Echo took off

Amazon released its first smartphone, the Fire Phone, and its voice-activated speaker, Echo, right around the same time in late 2014.

But while the phone was a major flop, costing Amazon hundreds of millions of dollars, the Echo has become a runaway success, building a cult-like following.

Amazon's SVP Dave Limp, who oversees the development of all Amazon hardware devices, says both the Fire Phone and Echo were "equally big risks," but there was one big difference: the Fire Phone failed to differentiate itself enough from the rest of the competitors.

"The phone segment is very well-served. And we didn't come out with a product at that particular point in time that was differentiated enough for customers such that it got the momentum that we needed to see," Limp said at the Fortune Brainstorm Tech Conference on Tuesday.

Limp pointed out that the Fire Phone saw good reviews when it was tested internally by Amazon employees. But unlike the Echo, which immediately took off with a completely new voice-only interface, the Fire Phone wasn't able to generate much traction.

"It just didn't resonate to the next level of masses. The phone segment is very large, and to be successful, you have to get to scale, and we were just unable to get to scale," he said.

Still, Limp lauded his team that developed the Fire Phone for taking a big risk because you'll never make it big in the tech industry without "swinging for the fences."

Also, while he declined to comment on future road maps, he didn't completely rule out the chances of another Fire Phone release in the future, saying, "Obviously mobile is important and something we pay attention to."

Disclosure: Jeff Bezos is an investor in Business Insider through hispersonal investment company Bezos Expeditions.