This is because according to reports, the Samsung Galaxy X (the name that is supposedly that of the phone), it will be a limited-run device with only 100,000 units produced. Not only will the phone be limited in terms of quantity, but it will be limited in terms of region availability as it is expected that Samsung could only choose to launch it in their home turf of South Korea.
As the report from Forbes notes, this isn’t the first time that Samsung has done something like this. The company had previously launched devices that were limited to certain markets as a way to test the waters before eventually expanding on its availability, meaning that the Galaxy X could just be the first of many phones to come that will feature a foldable display.
Recent rumors have suggested that the phone could be launched in 2018, but its reported launch date has been pushed back multiple times in the past so take it with a grain of salt for now.