Platforms lock users in by enclosure when data expansion alone fails.

Evidence

A third dominant tendency is the funnelling of data extraction into siloed platforms. When extensive means are not sufficient for competitive advantage, this approach tries to tie users and data to the platform by locking them in through various measures: dependency on a service, inability to use alternatives, or lack of data portability, for instance. — Nick Srnicek, Platform Capitalism, 91

Categorization

• DEFINE: Introduces the ‘siloed platform’/enclosure mechanism as the third expansionary tendency.