CanActivate vs. CanActivateChild with component-less routes

Question

The angular2 documentation about Route Guards left me unclear about when it is appropriate to use a CanActivate guards vs. a CanActivateChild guard

Answer 1

What if you have 10 children defined.

Then canActivateChild only needs to go in one place if they all have a common requirement, as opposed to 10 canActivate on each child.