Mostly because I only use them for a few things: Niche projects like oldschool Doom and DolphinVR, as well as Project Cars 2 and Elite: Dangerous. After thousands of hours into all of those? I'd say burn out. Lifestyle is another problem. I'm gone for work 1.5 to 3mo at a time and only come back sporadically until a 7-14day siesta, depending on how productive I feel. I do carry a gaming laptop and Rift S for lower end VR on the go, but lately have been leaving the headset at home as well. I'm just burned out in general.