Marketo Sales Insights Watch List Issue

In Marketo Sales Insights what is the criteria to have someone appear on your watch list? I have added several people to my watch list. Some of them will show up in MSI in the My Watchlist tab. Others will not. On the Salesforce Contact screen in the Marketo area of my screen, it does show that they are added to my watch list. Figure there is some sort of criteria filtering them off the My Watchlist area of MSI.