So either they were disqualified for being professional, or so unprofessional as to lose way too many battles.That's a good point... but they weren't that disciplined until around the time of Marius. Before that they were pretty much a militia and they lost as many battles as they won... eventually winning by sending another army to be slaughtered, then another, then another.
Not sure which is a bigger disqualifier for me (this is also why I rank the Norman knight highly... those guys won a lot)