In the course of two European projects the endurance behavior of stretchable electronic substrates and of electronic textiles was investigated. The results have to a large extent been published already. In this work new analyses to the earlier results are presented. Straightforward analytical approaches are used to describe fatigue under cyclic mechanical loading in the two technologies. For stretchable substrates the actual plastic strain upon stretching could be qualitatively evaluated to replace the engineering strain. For the textile-based substrates the bending strain was estimated. Additionally, there are sub-categories within each technology which perform differently and apparently show percolation behavior.