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by Agustus 2040 days ago
Metrics: It is easy for them to keep track of metrics, including the following:

* did someone pause on a post, mark it * time on page, * whatever other crazy metric you can show to advertisers * in-line advertisements

Also, the walled garden makes it so you get the endorphin hit of clicking the button and it can algorithmically entice you back with notifications and other engagements.