Not being able to open them properly (and to make it more awkward they open to the outside) of course doesn´t make it possible to clean the outside easy. I can´t pretend to be a big fan of window cleaning but as soon as it is not possible to do anymore (unless you have a huge ladder or know and pay someone who does) I´m obsessed with it. I hate the windows they use over there, I think they are pointless and give me a feeling of claustrophobia in the summer. They seem to have finally got rid of the guillotine-style windows where you didn´t dare leaning out of underneath unless you felt suicidal only to replace it with an equally useless system.
But it can get worse - some people think it is a good idea to "decorate" the outside of the glass with funny metal-like lines (I´m sure they have a name but I can´t think of it) which gives a fake medieval look... reminds me of the Dursleys and the only word for it is bourgeois. Hate it! 1:0 for Germany.
In 1650 Mr. Vermeer already knew of the joy an open window can bring...just wouldn´t happen in nowadays Britain ;-)