Google says the built-in microphone it never told Nest users about was 'never supposed to be a secret' (GOOG, GOOGL)

In early February, Google announced that its home security and alarm system Nest Secure would be getting an update — users could now enable its virtual assistant technology, Google Assistant.

The problem: Nest users didn't know a microphone even existed on their security device to begin with.

The existence of a microphone on the Nest Guard (which is the alarm, keypad, and motion sensor component in the Nest Secure offering) was never disclosed in any of the product material for the device.

Nest Gaurd Nest

On Tuesday, a Google spokesperson told Business Insider it had made an "error."

"The on-device microphone was never intended to be a secret and should have been listed in the tech specs. That was an error on our part," the spokesperson said.

Google says that "the microphone has never been on and is only activated when users specifically enable the option."

It also said the microphone was originally included in the Nest Guard for the possibility of adding new security features down the line, like the ability to detect broken glass.

Still, even if Google included the microphone in its Nest Guard device for future updates — like its Assistant integration — the news comes as consumers have grown increasingly wary of major tech companies and their commitment to consumer privacy.

Google bought Nest — which was initially known for its smart thermostat device — back in 2014 for $3.2 billion. It became a standalone company in 2015 when Google reorganized as Alphabet, but in February 2018, it was brought back into Google under the leadership of head hardware exec Rick Osterloh.

Read more: Google is reabsorbing Nest, the smart home company it bought for $3.2 billion in 2014

Today, Nest offers a variety of IoT products including smoke detectors, video doorbells, and security cameras.