Aggregation of Marginal Gains
The aggregation of marginal gains is the notion that small improvements (marginal gains) applied methodically (aggregation) compound positively. Compounding is good. With engineering systems, one might say “The better things get, the better they get.”
The converse is also true: for negative gains, the worse things get the worse they get.
Small things matter, effects compound.
Aggregating marginal gains is part habit and part process. Process provides guardrails encouraging positive gains and discouraging negative gains. Process also helps us become habitually more observant, always keeping an eye out for that small gain.