As stated on Appcues: “Product tours — sometimes called product walkthroughs — introduce users to a new product and help them find their bearings.” Usually, when it needs to showcase a new feature or complex UI functionality in a web app, the customer-success team would send a campaign email to all of its users. While this is a great way to create such awareness, some users might not have the opportunity to see the added feature; hence, the purpose of the email would be defeated.

https://www.smashingmagazine.com/2020/08/guide-product-tours-react-apps/