I think it is true that if you see the same sign over and over again that you stop 'looking' at it. Only if it appears slightly different do you look at it again.
For my University project I'm looking into non-universal communication, and although there are many pictograms which are universal, many are not. There are still lots of signs and symbols that we pass daily which should be more universal but are not. I think especially so in England were we tend to assume that everyone can speak English.
I'm thinking of creating a kind of teaser guerilla advertising campaign, which would be launched in London. This campaign would make a light-hearted attack on everyday items which are vital in providing a service or information, such as newspapers, signs, symbols, posters, etc. The aim of this campaign is to highlight how much we all rely on language everyday, if it weren't for language, how would we get our opinions across and how would the country run? What an uncomprehendible place our globalised world could be, if it were not for the intervention of Graphic Designers and translators!