The force working against engineering economics is the technical framing of engineering decisions. Engineers are trained to reason about technical properties — latency, throughput, consistency, availability — not economic ones. The translation to economic language feels like simplification, which engineers often resist. But the board cannot evaluate a latency improvement; they can evaluate a cost reduction per transaction at 2x volume.
Cost of delay is the most important concept in engineering economics that most engineering organisations do not use. Cost of delay is the value lost by not shipping something per unit of time. A feature that would generate ten thousand euros of monthly recurring revenue has a cost of delay of ten thousand euros per month. A three-month delay costs thirty thousand euros. An engineering investment that reduces the delay from three months to one month is worth twenty thousand euros. Without cost of delay, every engineering decision is evaluated against the cost to build, not against the value of building.