Because she believes in their own ideas, and I think that the decision made is based on the principles of reason. People should choose their own path. Should not follow others.
Because the speaker believes in the idea itself. And think what made the decision based on logic. People should choose their own path. Do not follow others.
Because the speaker believes in his own mind. And think what decide pretend things based on the main reason. People should choose their own path, should not do to others.