The name comes from the three co-founders. The H is for Hoglund (Greg). The B is for Bracken (Shawn). The Gary is for Jon Gary who left the company shortly after it was founded.
It is also indicative of how uncreative the founders were. To me, I intuit this as clear confirmation that it was a company founded with no strategy other than to suckle from the teat of defense spending.
How much you want to bet that the H. B. and G. of this company had ties/tenure in DoD or other governmental departments and were thus situated to reply to RFPs from their previous colleagues.