Closing the “diagnose-but-not-act gap”: a theory-practice comparison of HPO diagnosis trajectories

Purpose Quality improvement initiatives (QII) frequently begin with a diagnosis but stall in the “diagnose-but-not-act gap.” This article examines why diagnosis results do not reliably convert into owned, executed and closed improvement actions, and what a higher-fidelity conversion infrastructure looks like in practice. Design/methodology/approach The study compares what the quality/operations and change literature prescribes about diagnosis-to-action conversion with how high-performance organization (HPO) diagnosis trajectories unfold in practice. The comparison is organized around diagnosis phases and the governance routines that connect diagnosis outputs to prioritization, ownership, cadence and closure. Findings The comparison suggests that failure is less about the diagnostic instrument itself and more about weak conversion mechanisms: ambiguous decision rights, insufficient prioritization rules, unclear ownership, lack of a disciplined follow-up cadence and limited feedback loops that sustain learning and accountability. Effective trajectories show explicit translation of diagnosis outputs into a small set of owned actions, embedded in recurring performance dialogue and closure routines. Practical implications Managers should design diagnosis trajectories with an explicit conversion architecture (decision rules, ownership logic, cadence and closure discipline) before data collection begins, thereby increasing the probability that diagnosis leads to measurable improvement. Originality/value By conceptualizing the step between diagnosis and implementation as a conversion problem, and by examining this step in a corpus where the diagnostic instrument is relatively stable, the article offers a more fine-grained explanation of why ostensibly similar diagnosis exercises produce uneven follow-through.