The HP Pavilion x360 has an HDD storage medium which is better than most 2 in 1 laptops that are a comparable age to it. Most 2 in 1 laptops that were released around the same time as it have an SSD storage medium. HDD is a traditional storage drive which stores the information on magnetic disks. HDD drives are slower than other forms of storage such as solid state drives (SSD) and flash drives.
An HDD storage medium is in fact the worst storage medium amongst all comparable spec portable PCs that were released around the same time as the Pavilion x360.
The best storage medium amongst comparable types of laptop is SSD.