It is not so long ago that Jean Lannes, Duc de Montebello, inspired his troops into the breach once more at the Siege of Ratisbon by grabbing a scaling ladder and exclaiming
I was a grenadier before I was a marshal, and am still one.
Lannes had to be physically restrained from advancing forward to the breach, but his men took heart and, advancing into the breach for a fourth time, finally forced it and opened a gate for the remaining French forces to storm the city.
Four weeks later, May 22, 1809, Lannes was struck by a spent cannon ball during the Battle of Aspern and had to have both legs personally amputated by Napoleon's Surgeon General, Dominique Jean Larrey. He died eight days later from these wounds.
Likewise Julius Caesar won the Roman Civic Crown, its second-highest military honour, as a young man.
Leadership in combat is about inspiring one's followers to believe in victory; more strongly than the opponent's followers so believe, and there are likely as many ways to do so as there have been successful commanders through history. However dying, or even being seriously injured, in combat is not generally successful as one such technique.
Although not historical, Homer's Iliad tells us much of how the ancient Greeks viewed, and wished to be seen as viewing, their combat heroes and leaders. Achilles is the prototypical commander who leads through prowess in combat, but his hubris in that regard contributes to his death by the hands of Paris. in contrast Odysseus, renowned rather for his wiles, rhetoric, and archery, survives and eventually leads the Greeks to victory and eventually back to their homelands.
Yet as Homer relates the tale, the Greeks would have lost early without the combat skill of Achilles and Ajax, and late without the wiles of Odysseus. I believe this is a fair assessment of combat leadership. A successful army, even from the time of Homer until the modern day, required both types of leadership - by example in combat as well as by wiles and strategy behind the lines. Modern armies, much more numerous than ancient ones, have specialized these two roles into respectively Sergeants and Lieutenants for the former, Colonels and Generals for the latter.