It refers to a widespread and costly problem in industrial digital transformation. It describes the frustrating state where companies invest significantly in pilot projects for new technologies—like AI or IoT—but fail to scale them into full production. These pilots get stuck, unable to move beyond initial testing phases.

The World Economic Forum (WEF) frequently highlights this issue, recognizing it as a major impediment to achieving the full potential of Industry 4.0. They emphasize that a lack of clear strategic alignment, insufficient integration with existing legacy systems, inadequate change management, and a failure to demonstrate clear, measurable ROI at a larger scale are common culprits. Essentially, a successful pilot becomes a perpetual, isolated experiment rather than a catalyst for genuine, factory-wide change, hindering broader economic and societal benefits.