Navigation breaks at scale. What works for 10 pages fails for 100.
The Mega-Menu vs Sidebar
Sidebars allow for deep nesting but consume horizontal space. Mega-menus save space but can be overwhelming. For administrative UI, a collapsible, nested sidebar is almost always superior as it persists context.
Command Palettes
As systems grow, visual navigation becomes secondary to search. Implement a global command palette (Cmd+K) as the primary way power users jump between contexts.