Ugly buildings in Oxford

Whilst Oxford is renowned for its wonderful architecture  [Bodleian Library, Wrens Theatre, numerous college quadrangles etc. etc.]; it also has some ugly sisters. According to the site below, Oxford 'wanted to have some ugly buildings' from the 'post war' era. They are described as being not 'in sympathy' with their older neighbours. Is that what makes architecture ugly? - Not being in sympathy with something that went before coupled with being built after 1945....

http://www.oxfordlight.co.uk/photos/ugly-buildings-of-oxford/03/

The Westgate Centre and Car Park (photo from Oxford Lights)