The reason it's used is straight forward. Regulations.
Back in 2015, the U.S. Federal Aviation Administration (FAA) created a sub-250-gram weight category for drones. 250 grams was the decided weight after a committee of aviation and drone experts were tasked by the FAA to decide the minimum weight of a drone thats needed to be registered for recreational use.
Not long after other countries, Canada, the United Kingdom, continental Europe, and Australia agreed on this weight category and began to implement it into its laws and requirements.
As a result of the almost global uptake of the 250-gram weight category countries started to use it as the threshold for many drone regulations as it is considered to light to pose a safety risk.
Take a look at some of the drones we sell that are under 250 grams on the right.
If you are interested in learning more about the 250-gram category and the history behind it, take a look at our blog post on it.