For website owners, how does the subscription model usually…

What are the main things webmasters and advertisers should consider when using push notifications as a way to communicate with users? I’m particularly interested in how these alerts compare with other online advertising formats, since they appear directly on a user’s device and can include both an image and a short message before someone reaches the final landing page. For website owners, how does the subscription model usually work over time, and what should be considered when evaluating revenue-sharing arrangements? For advertisers, what types of products or services are generally better suited to this format, and how can they avoid making notifications feel intrusive or irrelevant to users?