Here's my understanding: If you're over-committing memory then you don't find out your program ran out of memory until you try to access memory you've previous

Here's my understanding: If you're over-committing memory then you don't find out your program ran out of memory until you try to access memory you've previously "allocated". If you're not over-committing, then you'll find out your program ran out of memory on an allocation where you might be better prepared to handle it.