In some cases, the hyponychium can grow more than usual, causing discomfort, but be assured it's completely harmless, as Knight tells us: "The growth of this skin can occur for so many reasons, one of the most common is trauma to the nail bed as this can cause the skin there to thicken as a protective mechanism."
Notton echoes this, explaining that skin conditions and fungal infections can lead to build up and thickening of the hyponychium and the nail bed. "The skin condition, Psoriasis, which is where skin cells grow faster than they usually do, can make the Hyponychium grow, as can fungal infections, which thicken the nail and skin tissue beneath the nails.
"Like all other features of the body, our Hyponychium and nail beds vary from person to person thanks to genetics. However, some lifestyle factors may also determine the length. In short, the care you put into your nails can really determine their health. For example, if you're more prone to nail trauma (whether it's through work, or nail biting), your nail bed can be affected, so it's important to take care of them."