There is always some one better and some one worse than you at everything, that's life. Should we deceive students making them believe that they will always get

There is always some one better and some one worse than you at everything, that's life. Should we deceive students making them believe that they will always get good grades? Maybe we should just skip this and lower the standard? I think it's better that we strive for excellence even if we don't achieve than we strive for a false accomplishments (mediocrity).