Admitting and correcting our mistakes keeps us in our own good graces, as well as of those we love and care for. It returns us to the proximity of perfection. Part of the burden of leadership is that the circle of people to whom we bear responsibility for mistakes is wider. Leadership requires us to love and care for those within that circle, and to admit and correct our mistakes. Or else we do not deserve that mantle.
The White House presumes that its current occupant and advisors are infallible. It refuses to admit, much less accept responsibility for or correct any mistakes whatsoever. The buck is passed, the fall guy is a private, and private citizens pay the piper.