Breadcrumb levels

After reading the documentation, I’m having trouble understanding what the use of the “level” is for breadcrumbs. If an event has a particular level but its breadcrumbs have a different one, will some potentially not be shown?

The event’s level determines what events to show (filtering), and the breadcrumb’s level determines how that breadcrumb is shown within the event display (as the docs state it, by (de-)emphasizing).

Thanks for this info. Can you provide documentation to breadcrumbs beyond the basic add_breadcrumbs exemplar. I tried that and was unsuccessful finding my breadcrumb being reported. Perhaps I am missing something.