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The answer to the question of what prompted Hans Emmenegger to document his painting technique in detail can already be found in his very first logbook entries from February 1901. These describe systematic glazing experiments with the tube paints of the Mussini variety, which he diluted with varnish. Even after the first series of experiments, which incidentally worked well, he noted doubtfully in the logbook: "Will these varnish-mixed paints perhaps crack, darken or yellow?"

That Emmenegger wanted to work on the effect of his paintings and avoid mistakes that endangered their durability is attested to by numerous other passages in the painting technique notebook. Like many of his contemporaries, he was concerned about the durability of his works. Clearly, he had experienced their paint layers cracking and flaking off, certain sections forming early shrinkage cracks or even discoloring. Such damage had always occurred at a time when he did not remember the work process well enough to be able to reconstruct its causes. The painting technique notebook was his memory aid. It was supposed to help him distinguish good from bad products, recognize materials that were incompatible with each other, and avoid technical mistakes.

By the way, the question why he gave up his logbook in July 1905 was answered by the painter himself. After his last entry of June 23, 1905, he noted that it would "not be continued, since its usefulness seems out of proportion to the work it causes." He could not have foreseen that his notes would later form a testimony that provides far-reaching information about the technique of painting at the time of early modernism.