Why use cement render?

It still amazes me. This cottage has been rendered with cement render, it is beginning fail and reveal why. The building is made from stone, with lime mortar in the joints of the stone. If you look at the hole where the render has fallen away, you can see what beautiful stone lurks begins the cement.

This photo was taken in a village where all the houses are made from the same stone, provide a very pleasing character. So why render? To be different? Was it a good sales man who called? I suspect it was a small sign of damp or a problem inside the building and they thought that if they 'water proof' the building with cement the problem would go away,  I suspect it didnt work, as all te cement would do it trap the moisture inside the building, a building which was building to breath moisture in and out. 

These buildings need to breath and they work with moisture being drawn in and let out through the open pours of the lime joints between the stone. this just creates a build up of moisture behind the impervious render, pushing the render off and making the stone fail. It will also make the interior of the house damp. It also affects the charecter of the house and the village, with the rest of the houses with their richly coloured stone on show.