Open Rate is a KPI that evaluates the following kind of placement:

Open Rate is a key performance indicator (KPI) specifically used to measure the effectiveness of email marketing campaigns. It calculates the percentage of recipients who opened a particular email out of the total number of emails delivered. A higher open rate indicates that subject lines and sender names are engaging and that the emails are successfully reaching the inbox. Gift list placement, cashback event placement, and category placement are not directly measured by "open rate." While these might involve communications that could be sent via email, "open rate" itself refers to the act of opening the email, not the performance of the placement type within an email or on a website. These other placements would have different, more relevant KPIs, such as conversion rates, click-through rates, or redemption rates.