What helped the small army of Greeks defeat the Persians?

The Greek army had a good organization, the Greek soldiers were well armed and trained, fighting in a close formation – a phalanx. The Persian army was very numerous, but it lacked organization and discipline, since there were warriors of different peoples who were armed and fought in their own way. An additional reason for the victory of the Greeks was that the Greeks took advantage of the advantages of place and time. For example, the Greeks attacked the Persians after they landed on the shore after a long journey.