To unsubscribe means to cancel a service or to remove oneself from a digital mailing list. An unsubscribe method is a common part of email marketing or similar setups. These features help to provide an option for those who do not want to receive further emails or communications about a company or its products or services.
Techopedia explains Unsubscribe
The assessment of unsubscribe methods is part of a comprehensive review of a business or project. Unsubscribe methods that are too complicated can leave businesses open to perceptions of forced service or communications. A well-designed unsubscribe method can leave potential customers and respondents feeling much better about their interactions with a business online or through digital technology.
One issue related to an unsubscribe method is the original opt-out method. This is often present when companies actually collect the data for email or service marketing, often in the form of a check box. One common question about a company’s opt-out is whether the form or other interaction contains a check box that a user must actively check to receive future communications, or whether the check box comes pre-checked, and will send out email marketing or other direct communications to a user as a default setting. Again, pre-checked boxes and other similar defaults can leave users with the feeling that they have been tricked into receiving email marketing or other communications.