I should tell this to my batteries that did not know that they should not get drained. Ah, the case! It is held together with a duct tape as it fell apart after a short use. No, it was never left aside in a pile of tools. Mitutoyo, treated exactly in the same manner, maybe had one battery change since it was bought while HF consumed sheets in a comparable time. In my book, the tools are for solving problems, not for producing problems of their own.