It may correspond to availability of the satellite to take the photos of the area.<p>First the satellite has to be over the area.  Second the satellite has to be free from other tasks to take photos of the area.  From Wikipedia, the satellite&#x27;s mission involves:<p>Proba-V will support applications such as land use, worldwide vegetation classification, crop monitoring, famine prediction, food security, disaster monitoring and biosphere studies.<p>Taking photos of a single lake in Bolivia may not be high on that list of priorities.