Describe what a state reset is

Signed-off-by: Aaron Raimist <aaron@raim.ist>

specification/rooms/v1.rst

@@ -89,8 +89,14 @@ State resolution
 ~~~~~~~~~~~~~~~~
 
 .. WARNING::
-   Room version 1 is known to have bugs that can cause the state of rooms to reset.
-   This is fixed in room version 2 and later.
+   Room version 1 is known to have bugs that can cause the state of rooms to reset
+   to older versions of the room's state. For example this could mean that users
+   who had joined the room may be removed from the room, admins and moderators
+   could lose their power level, and users who has been banned from the room may
+   be able to rejoin. Other state events such as the the room's name or topic could
+   also reset to a previous version.
+
+   This is fixed in the state resolution algorithm introduced in room version 2.
 
 The room state :math:`S'(E)` after an event :math:`E` is defined in terms of
 the room state :math:`S(E)` before :math:`E`, and depends on whether