College conference membership once tracked geography and rivalry. It now tracks media value, because the money that funds athletic departments arrives through collectively negotiated broadcast agreements.
Media rights are sold by the conference
Individual schools generally do not sell their own football and basketball broadcast rights. The conference packages them and distributes revenue among members.
That pooling makes the conference the unit of value, so a broadcaster is buying a portfolio of programs, dates and audiences rather than a single team.
Distribution formulas vary, but the resulting per-school payout is the number that drives decisions, since it dwarfs ticket and donation revenue at most programs.
Adding a school changes the math
A conference considering expansion asks whether a candidate increases total rights value by more than the additional share it will consume.
Value comes from national audience, from an established brand that draws viewers regardless of opponent, and from access to a television market the conference lacks.
A school that merely adds games without adding audience dilutes the pool, which is why competitive quality alone does not secure an invitation.
Exit costs slow the movement
Conference agreements include grants of rights, under which a school assigns its media rights to the conference for a fixed term regardless of membership.
Leaving before that term expires means the departing school's games may still belong to the old conference, which makes the move economically painful.
Notice periods and exit fees add further cost, and negotiated settlements are common, which is why announced moves often take effect seasons later.
Travel and non-revenue sports absorb the cost
Realignment has produced conferences spanning multiple time zones, and the football schedule that justifies it is only a fraction of the athletic calendar.
Volleyball, baseball, soccer and track teams travel the same distances with far smaller budgets and athletes carrying full course loads.
Conferences respond with regional scheduling pods and reduced round-robin formats, which limits travel while diluting the idea of a single conference standing.
Rivalries are the collateral
Long-running rivalry games are among the most valuable individual properties, but they are frequently casualties when the schools land in different conferences.
Some are preserved through nonconference scheduling agreements, though those compete with the limited number of games available in a season.
The underlying pattern is that conference membership now follows the terms of broadcast agreements, which are renegotiated periodically and reset the incentives each time.