When adding restrictions to segment(s), the default selection in ENTIRE segment (in other words, all lanes).
If, for some reason. the editor misses this setting, the segment will be excluded (by mistake) for navigation for certain vehicles.
For instance, adding BUS lane for all lanes will prevent private cars from using this segment. This would lead to wrong and strange navigations.
For that reason, and especially since, after saving, there is no visual mark in WME for this selection (ENTIRE vs specific lane) it is advised to add a popup warning message for these cases, like the warning message that pops up if "near HOV" is selected for RTCs.