40-40-20 Rule (direct mail)

Biological Parallel

Successful predation requires three components: prey selection (40%), hunting strategy (40%), and execution skill (20%)—a cheetah targeting the right gazelle with optimal approach succeeds even with imperfect sprint; choosing wrong prey dooms even perfect execution. Energy allocation in predators follows this asymmetry: most investment in detection and positioning, minimal in the final strike. The 40-40-20 split reflects that upstream decisions constrain downstream outcomes, a principle from foraging theory where search and assessment dominate harvest in determining net return.