The acronym BLUF stands for Bottom Line Up Front.
This term derives from recipients of interminal briefings saying "Just give me the Bottom Line". This led to the supervisors of the briefers telling them to give the "Great Man" the bottom line up front, so as to get it over and done with.
From Wikipedia we have this
B.L.U.F. is an acronym (alternatively, initialism) for "Bottom Line Up Front". The term is common in US military writing.&nbasp; The concept is not exclusive to writing; it can also refer to conversations and interviews. Traditionally, conclusions and recommendations are included at the end of a text, following the arguments and considerations of facts. A 'BLUF' is a paragraph detailing the conclusions and recommendations at the beginning of the text, in order to facilitate rapid decision making. This differs from an abstract or executive summary in that it doesn't necessary summarise the arguments or evidence included.