What is a not invented here mentality considered in Integrated Product and Process Development IPPD according to Defense Acquisition University DAU?

A "not invented here mentality" is considered a barrier to Integrated Product and Process Development (IPPD) implementation.

In simple terms, it means, humans shouldn't turn off their brains and believe that, just because something doesn't exist, that this something cannot exist. Businesses must practice being innovative or inventive. If we have a "not invented here mentality", then, we lose opportunities to create and expand.