In the Napoleonic Wars the other major powers of Continental Europe, especially Austria but also Prussia and Russia, seemed to keep coming back every few years to have another go at fighting Napoleon, no matter how many times he had beaten them before. Why?
Could they not see after he had won his first few battles how hard he was to beat?
I leave the period from 1813 out of this question as it is more understandable that countries would dare to oppose him once the exceptional cold of the Russian winter and the vastness of the country had helped the Russians to destroy Napoleon’s immense invading army.
I have also confined this question to the Continental European powers, as Britain protected by the sea and its Navy, could more safely defy Napoleon.