the transparency of PB
As far as I understand, the transparency of PB is to constantly update the necessary details
it is true?
Or does it need to be updated at the sprint review when there are both scrum team and stakeholders?
Thank you in advance for the help.
Each Scrum event provides a formal opportunity to inspect and adapt certain things, but it is not necessarily the only opportunity.
Transparency is about making the work and the state of the work visible to all the relevant stakeholders. If there is transparency, then no one needs to ask other people for the relevant information. Instead, anyone who needs to know something can just go look. In the case of the Product Backlog, transparency is more than just updating the details of the Product Backlog Items and keeping those details accurate. It's about making sure everyone can see the Product Backlog, understand the ordering of the work, and use the state of the Product Backlog to make decisions.
Updating the Product Backlog is an ongoing activity. Although the Sprint Review is a formal event to inspect and adapt the Product Backlog, the Product Owner and the other members of the Scrum Team are likely communicating with key stakeholders at other times as well. These conversations and a changing knowledge of the state of the world can result in updates to the Product Backlog.