Unlike most video games, which are usually navigated using various free-ranging human interface devices, virtual worlds are usually navigated (as of 2009) using HIDs which are designed and oriented around flat, 2-dimensional graphical user interfaces; as most comparatively-inexpensive computer mice are manufactured and distributed for 2-dimensional UI navigation, the lack of 3D-capable HID usage among most virtual world users is likely due to both the lack of penetration of 3D-capable devices into non-niche, non-gaming markets as well as the generally-higher pricing of such devices compared to 2-dimensional HIDs. Even those users who do make use of HIDs which provide such features as six degrees of freedom often have to switch between separate 3D and 2D devices in order to navigate their respectively-designed interfaces.
Like video gamers, users of virtual world clients may also have a difficult experience with the necessity of proper graphics hardware (such as the more advanced graphics processing units distributed by Nvidia and AMD) for the sake of reducing the frequency of less-than-fluid graphics instances in the navigation of virtual worlds.