Why would someone be chosen to be a party leader (in government)?

what does someone have to do to become a political party leader in canada? like why would they be chosen?|||To lead their party to victory. Someone who was good at handling the news media and telling the public where the party stood on issues. Dealing with party politics, trying to smooth out rough edges within the party. Someone that people within the party and general public could admire. Someone who could settle all the in-fighting that goes on.