The correct answer to this open question is the following.
Your question is incomplete. You did not provide the excerpt or any specific reference for the context, the speech, the time, the article, or the book.
However, trying to help you, we did some research and found the following speech. If that is the case, we can comment on the following.
"The disorders and miseries which result gradually incline the minds of men to seek security and repose in the absolute power of an individual; and sooner or later the chief of some prevailing faction, more able or more fortunate than his competitors, turns this disposition to the purposes of his own elevation, on the ruins of public liberty." (George Washington).
So Washington's main reason for making the statement was that he was worried that the leaders of political parties would act out of self-interest, dividing the nation into factions.
On his final days as United States President, George Washington publicly expressed concern on the issue of political parties. He was against political parties because it could form factions that defended their own particular interests and agendas, and could create an unnecessary division between the citizens of the country.
