Start with intent.
What did the person come to do? Find a product. Save a lead. Compare an option. That intent is more useful than a page-view count. Design around it.
Remember the useful thing.
A saved item, a clear history, or an unfinished task gives the next visit a place to begin. Make it easy to pick up where the person left off.
Send a signal, not noise.
An alert should carry news. A price fell. A lead changed. A result is ready. Give people control over what they receive and how often.
Close the loop.
Bring people back to the thing that matters. A sale alert should open the saved product. A field update should open the lead. Remove the work between the message and the action.