Undoubtably, Napoleons tendency to lead from the front struck a chord with his men, as did his sharing of his mens hardships.
Many factors led men to follow him.
Often overlooked is the fact that Napoleon actually paid his men in something other than promises. For the first time since before
the Revolution, soldiers received payment. Campaigning offered a real chance of riches, not just for the higher ranks, but
also for the ordinary rank and file. A soldier could loot many times the average labourers pay and higher ranks could acquire
beautful art-collections etc. and become very wealthy men.
Napoleons bulletins and propaganda were carefully worded, and, although its easy to be cynical now, genuinely inspired his men.
Men were actually brought to tears by his rhetoric, and its claims of immortal glory etc.
The Legion of Honour also endeared many to him. It was a universal incentive to fight - many prefered the Cross itself to the
1200 franc pension which accompanied it, and, unlike other armies medals of the time, anyone could earn it.
Campaigning meant deaths, which meant oppurtunities for promotion. There were very few oppurtunities for promotion during peace
and many considered the risk of death acceptable as it also carried oppurtunities for promotion as officers were killed. This was
part of the reason they followed him during the hundred days - the Bourbons meant an end to campaigning.
Perhaps the most important reason they followed him was because he won. True, he suffered some setbacks, but by and large, soldiers
stood a good chance of winning under him. And since he nearly always fought in enemy territory, this meant more chances for looting. A successful general is always popular.
Napoleon also created a myth of infallibility concerning himself - he blamed 1812 on the elements, 1813 on his Marshals, 1814 on
Marmont, and 1815 on everyone: many soldiers believed that he personally, wasnt responsible for his defeats.
This is probably an oversimplification, but these factors certainly played a part.