Mechanochemistry is rapidly transitioning from a green alternative to a powerful tool in organic synthesis. Yet, the persistent “black box” nature of ball milling, where kinetic energy is often treated as an empirical variable, limits its predictive use. To move from trial-and-error toward guided synthesis, a deeper understanding of how mechanical force triggers organic transformations is essential. We demonstrate an experimental approach to isolate the individual drivers of mechanochemical reactivity. Using a standardized mixer mill setup, we disentangle the roles of single-impact energy (Eimpact), cumulative energy (Etotal), liquid-assisted grinding (LAG), and secondary effects. By investigating two distinct all-solid reactions, the Wittig olefination and the Finkelstein halogen exchange, we reveal a fundamental duality in mechanochemical pathways. The Wittig reaction behaves as an impact-complete system: conversion occurs exclusively during active milling and scales linearly with Etotal, making it a robust benchmark for energy scaling across milling devices. In contrast, the Finkelstein reaction is impact-triggered, where mechanical force initiates a process that continues through post-impact aging. Rather than treating aging as an uncontrolled process, we quantify how its rate and extent correlate with Eimpact, enabling high conversions with reduced overall energy input. Finally, we address the question of whether LAG-enhanced diffusion outweighs the role of impact energy. Our results prove that LAG does not replace the impact-driven regime but modulates it by balancing energy transfer with enhanced diffusion, clarifying the elusive LAG sweet spot. By isolating and quantifying these mechanochemical drivers, we provide a framework for controlled and reproducible organic mechanosynthesis, shifting the field toward guided control of mechanochemical transformations.