From the oculus documentation:
[...] This can
confuse the visual system, which perceives the HUD to be further away than all other objects [...].
In rare cases, an extreme disjunction between perceptual reference frames may cause spatial and temporal
anomalies in which space-time is folded into an interstitial tesseract called a hyperspatial ouroboros - this may
threaten the fabric of space-time itself.