The Spotlight is a play to help create focus. Sometimes hard decisions must be made. This play is a 'converging' activity. This can be helpful to narrow down options, ideas, tasks, etc.
We can use a Spotlight on a Product Backlog.
It’s generally a good idea to keep the Product Backlog short, clear and focused. The Product Goal helps achieve that. It serves as a spotlight. If (new) needs are not in the spotlight, they may not (yet) be needed in the Product Backlog. Refine just-in-time.
“The Product Goal is in the Product Backlog. The rest of the Product Backlog emerges to define “what” will fulfill the Product Goal.”
- The Scrum Guide.
There may only be one active spotlight at a time as the Scrum Team must fulfill (or abandon) a Product Goal before taking on the next. This ‘Spotlight’ can also serve as a visual way to show stakeholders what the Scrum Teams are focussing on. It helps to clearly illustrate the decisions a Product Owner makes in regards to what goes in or out of the Product Backlog and how the items (PBIs) are ordered.