Several properties of a Window can be set programmatically, but are ultimately under control of the platform. Such properties include a window's position on the screen, its size, its stacking order relative to other windows, and whether or not the window is iconified or maximized. Many platforms have a window system that allows these properties to be specified by the program, but then allows the end-user to alter them.

By way of example, a window's initial position and size can be specified, but the end-user can later drag or resize the window, which will affect the values of these properties. A tiling window manager might even move and resize a window from its initial position and size in order to not overlap another window. Similarly, the stacking order and whether or not a window is iconified or maximized can be altered by the end-user. Some systems (e.g., mobile or embedded systems), have a fixed position and size that can't be changed by the application at all.

The specification of these properties should be clarified to indicate that their values can be changed or ignored by the platform. Several of the properties already have a comment to the effect that the value can change externally, and thus the properties are not bindable, but this should be clarified further and for all such properties.