I will certainly not be disclosing a secret when I say that collecting geo-information is a tedious and labour-intensive business. Indeed, 80% of the cost of most GIS projects concerns the data gathering part. Topographic data for compiling, say, 1:10,000 maps, is exclusively put together by highly-skilled professionals, either employed by the (national) mapping agency itself, or hired by the same. Consequently, updating of topographic databases is a costly and time-consuming endeavour and the frequency of updating is accordingly measured in years rather than in months. And this in a world in which the rate of change in major areas has never been so fast, not only as a result of population pressure, but also thanks to high levels of economic activity due to political relief or foreign support.
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