Recruiters used to have it a little bit easier. They knew where to find the best and brightest. They could rely on the signals conveyed by the most selective institutions—Ivy League and the like. If they managed to hire people from these institutions, their job was generally done and the recruits were generally suitable.
Choosing to externalise or internalise an activity has long been a key strategic concern for companies. One that consulting firms made a business of supporting, providing tools and ready-made thoughts to help companies make their strategic choices. The dominant dogma has long been that they should focus on their core business and outsource everything else to other specialised companies.