Think of a DEX aggregator that integrates 10 exchanges. A user swaps through just one of them.
Before AIP-127 (Eager Loading):
The VM charged gas for every module you could reach, even if your transaction only executed one code path.
Now (Lazy Loading):
Modules are loaded and metered on first use, so gas reflects what you actually execute.
What this means:
Integrate more protocols without hitting dependency ceilings
Users pay less gas in the common case
Fewer surprise failures from upgrades you don’t control
Faster cold starts (fewer cache misses)