A clean quantitative framing is this: most event-driven positions fail not because the thesis is wrong, but because the timeline slips. Mechanism: Corporate events — regulatory approvals, deal closes, restructuring completions — are subject to delays that erode the economics of a time-sensitive position. Why it matters: That is why event-driven investing requires explicit hedging of time risk, not just directional risk. Market translation: A merger expected to close in Q2 that slips to Q4 can halve the annualized return of the spread, even though the deal eventually completes. Failure mode: The mistake is sizing an event position based on the announced timeline without building in a delay buffer. Review question: Ask whether the market is mispricing the mechanism or simply narrating it loudly. That is usually where the edge is: not in the vocabulary, but in the structure underneath it.