It is no secret that the Battle of Waterloo doomed Napoleon's ambition, but why did his military force fail? After all, Napoleon's military expertise was greatly famed.
Marshal Grouchy, the last Marshal of Napoleon's empire, was not actually present at the Battle of Waterloo, but decided to pursue the Prussian army, despite hearing cannon fire at Waterloo. While Grouchy places the blame for the defeat on the lack of communication and coordination among the French army, one might wonder if the Battle of Waterloo would have gone differently had Grouchy gone toward the cannon fire instead of pursuing the Prussian army.
John Codman Ropes said, in his The Campaign of Waterloo, that Napoleon made critical errors that cost him the battle. Specifically, Ropes stated that if Marshal Ney had carried out his orders without hesitation, the campaign would have been finished on June 16, 1815. If Ropes is correct, then the Battle of Waterloo, which occurred on June 18, 1815, would have never happened.
There were crucial military decisions that affected the outcome of the Battle of Waterloo for the French army. If the French army had been more successful in the days before the battle, it might have succeeded in its campaign.