Loss of interest change of relevance
It happens to everyone. We lose interest in a topic, product, or service or the content sent in email is not the content promised. Just by sheer laziness, it may seem easier to redirect such emails to the Junk folder or just hit delete. Some list members do not unsubscribe, because they don’t trust the unsubscribe option, or they may be waiting for better material from the sender before they engage with the sender’s email again