Google has announced the main reason why it had decided to delay the launch of the Project Ara modular smartphone.

According to the tech giant, the prototype model of the device kept falling during stress tests, CNET reported.

Originally, the Project Ara handset was supposed to debut in Puerto Rico sometime this year. However, Earlier this week, Google decided to cancel the device's launch and said that it is having a hard time moving forward from the prototype's design.

Also, the company is currently looking for a location in the in the U.S. to test Project Ara, which strongly indicates that the customizable handset will not arrive in Puerto Rico, GSM Arena has learned.

Then, on Wednesday, Google announced the results of the tests conducted on the upcoming device. According to the company, Project Ara failed its drop tests.

"No more electropermanent magnets," the company tweeted with the hashtag #FailedTheDropTest.

These magnets hold the different modules or panels of Project Ara's components. Since one of the main selling points of the device is its modular design, which will allow users to upgrade the smartphone by swapping out the modules, Google needed an easy way to assemble and disassemble the handset.

Through magnets, the company was able to deliver a prototype model composed of hardware modules that easily snap into place. Once all of the modules are inside the smartphone's frame, a simple tap on the touch screen will activate the electropermanent magnets to keep everything in place, according to Gizmodo.

However, based on Google's tweet, it seems the magnets are not strong enough the keep the panels together. As reported by various sources, the device kept on falling apart once dropped.

This is a major setback for the Project Ara initiative because the magnets play a central role in the overall design and appeal of the modular smartphone. And, given the results of the tests, it seems Google has dropped the idea of using electropermanent magnets for the device.

Fortunately, developers of Project Ara were able to find a way to keep everything together. However, they did not explain how the new technique works.

"We are testing a signature experience to attach/detach modules," the developers tweeted.

It is not yet confirmed if these also rely on magnets or if it had already been subjected to drop tests. Hopefully, Google and the team behind Project Ara will release more information regarding their progress on the modular smartphone within the next few weeks.