Why did Napoleaon lose the Battle of Waterloo?

Answer 1

Perhaps because he delayed his attack for four hours because of the previous night's rain.

It may have been because of the less than well trained French force because of the lack of seasoned NCO's.

Possibly because of the pluck, valor, skill and training of the UK troops.

Some blame it on the French reliance on muskets instead of the longer range, more accurate and lethal rifle that many UK units used.

The arrival of the Prussians in the nick of time was relevant.

Wellington said it was a close call, so perhaps it was his lucky day, and a bummer for Napoleon.