The same issue as reported to ui-router also exists in ngRoute: angular-ui/ui-router#1766

The scope for the landing route is retained in the heap even when that state is navigated away. See the below for an example:

http://plnkr.co/edit/tS1z9PgWM927a3joiC95

Navigate to route B, then perform a heap snapshot. Both SibAObject and SibBObject will be on the heap. However, landing on '/home' first, then navigating between /home/a and /home/b allow the scopes to be dereferenced and freed correctly.