According to the Salesforce documentation, a prospect's score can be changed through automation rules, scoring model changes, or completion actions. A prospect's score is a numerical value that indicates the level of interest and engagement of a prospect, based on their activities, such as opening an email, clicking a link, or submitting a form. A prospect's score can be changed by using different methods, such as:
Automation rules: An automation rule is an automation tool that can be used to update a prospect's score when the prospect meets certain criteria, such as prospect field values, activities, or scores. For example, an automation rule can be created to increase a prospect's score by 10 points when the prospect visits a specific web page.
Scoring model changes: A scoring model is a feature that allows users to customize the scoring rules for different types of activities, such as email opens, form submissions, or custom redirects. A scoring model can be changed by editing the default scoring model in Marketing Cloud Account Engagement, or by creating a custom scoring model for a specific group of prospects. For example, a scoring model can be changed to assign more points to an email open, or to create a different scoring model for prospects from a certain industry.
Completion actions: A completion action is an automation tool that can be used to adjust a prospect's score after the prospect successfully completes a marketing element, such as submitting a form, clicking a link, or visiting a web page. A completion action can be used to increase or decrease a prospect's score by a specific amount, or to reset a prospect's score to zero. For example, a completion action can be created to decrease a prospect's score by 5 points when the prospect unsubscribes from an email.