I am wondering whether an "Executive Summary" is intended for an Executive, or whether it has another meaning. Most reports I read are not, as far as I know, intended to be read by anyone in top management, so it seems unlikely that they would have a summary intended for them.
A google search for "executive summary etymology" led me to wiktionary, where it states the etymology of the phrase is...
executive + summary
I didn't find this particularly helpful...
The wiktionary page on "executive" gives definitions as an adjective and as a noun, none of which make a lot of sense to me for use to describe a summary of a report:
1.Designed or fitted for execution, or carrying into effect.
2.Of, pertaining to, or having responsibility for the day-to-day running of an organisation, business, country, etc.; as, an executive act, an executive officer, executive government.
3.Exclusive. an executive bathroom
1.A title of a chief officer or administrator, especially one who can make significant decisions on her/his own authority.
2.That branch of government which is responsible for enforcing laws and judicial decisions, and for the day-to-day administration of the state.