Learn Finnish: Suositus yksilöityy datasta, jota keräämme. - The recommendation becomes individualized from the data that we collect.

It is built from the noun yksilö (individual) and the automative suffix -öityä. This suffix transforms nouns into verbs that describe a process or adaptation, meaning the subject undergoes the change itself. Here, it means to become individualized or tailored to a specific person.

If yksilöityä means 'to become individualized', how would I say 'to individualize' something?

You would use the causative suffix -öidä to create the transitive verb yksilöidä. While yksilöityä describes something changing on its own, yksilöidä is used when an external agent does the action to an object, such as a company individualizing a service.

Why does the sentence use the elative case datasta (from data) instead of another local case?

The elative case (-sta/-stä) is used because the data is the source material out of which the recommendation emerges or is built. Finnish typically uses the elative for things originating, developing, or transforming out of a core source.

Why is the relative pronoun jota in the partitive case?

The pronoun jota refers back to the data, acting as the object of the relative clause's verb keräämme (we collect). Because the collection of data is an ongoing, unbounded process and the data itself is an uncountable mass, the object must take the partitive case.