Acquiring new B2B buyers costs five to seven times more than retaining existing ones. Operators trapped on the "perpetual acquisition treadmill" lose money when churn cancels out new customer gains. Account management must transform from administrative cost center to strategic function multiplying lifetime value. Modern B2B buyers complete 69% of their purchase journey before contacting sales and maintain competitive shortlists ready for switching. LTV calculations require monthly revenue, gross margin, retention rate, and relationship lifespan. The "shield and sword" framework for retention and expansion shows how meeting high expectations creates deep loyalty while failure triggers rapid exits to pre-researched alternatives.