1.
Misaligned incentives destroy partnerships. When Quiznos profited from high franchisee costs instead of franchisee success, trust eroded and the system collapsed.
2.
Win-lose deals work until they don't. Eventually the losing side figures it out, revolts, and the whole structure falls apart.
3.
Debt magnifies decline. As revenue shrinks, servicing debt becomes impossible — $900M in debt became an anchor dragging Quiznos under.