an 'ugly duckling' that has become a beautiful swan [=an ugly/unsuccessful person or thing that has become beautiful/successful]
('informal') That dog of yours is '(as) ugly as sin'. [=very ugly]
The house is an 'ugly duckling', but it has a lot of potential.
(..) They said I could have any producer I want and I want you One committee source called it a $ billion metal sculpture too ugly to look at and too big to bury Over time, however, costs have doubled Did you write this? I write for you sometimes (..)1987 Broadcast News