What pattern distinguishes Tier 2 consortia that survive from those that don't?

A subsidiary question under Q-0004 (cost structure across tiers). Q-0012 asked the economic-conditions question at the Tier 2 level; Q-0032 asks the operational-pattern question that determines which consortia last.

The answer is C-0030. Proportional fees, easy ingestion, and automated contribution produce consortia that survive — CLOCKSS has operated for 20 years, LOCKSS for 27, HathiTrust for 18. Flat fees, difficult ingestion, and voluntary contribution produce consortia that don't — DPN charged $20K/year flat regardless of size and shut down in 2018; MetaArchive's flat fiscal-host increase converted to dissolution in 2025.

The economic risk at Tier 2 lives in the organizational model the fees fund rather than in the fees themselves. The fees are modest for research universities. What kills Tier 2 consortia is the mismatch between operating-cost growth, member-recruitment difficulty, and operating-reserve requirements.

The consortia that last are the ones in which the economics make participation rational at the institutional level. The consortia that fail are the ones whose model imposes member friction without delivering proportional value back to participation. The Tier 3 alternative — participation cost effectively zero, infrastructure already operating at idle, no consortium-level economic dependency — does not face this same bounded-by-economics constraint.