What does the acronym HARD stand for in Railway culture, and which value proves most costly?

HARD stands for Honor, Acceleration, Reliability, and Directness. Acceleration and Reliability are essential for infrastructure, but Directness is often the most emotionally demanding to maintain. It requires telling teammates radical truths about code quality, strategy, and operational performance without softening the message to avoid temporary discomfort. High-performing cultures require absolute clarity over politeness.