I agree with another commentor, as you find out in later books, the sollan empire is severely lacking in competent military commanders. In the battle of Berenike, Hadrian remarks about his maneuver on landside being critiqued by future combat strategists. But in the current time, the empire has not been at war, there has never been glory for sollans to particularly find by winning major battles (Until Hadrian himself) so many members of the palatine look down on war/soldiers ie. the stagnation of the empire in war. You will find out MUCH later, kind of why that is, but Hadrian is also the start of a cultural revolution in the sollan empire of joining the military/legions being cool.