Malfunction of X2 and Y2 capacitors

The increasing malfunction of X2 and Y2 capacitors is not only based on manufacturers errors or incoming wetness. The quality of many manufacturers is high but nevertheless malfunctions increase. It is nothing to wonder about when devices work at 100% in the beginning and after some weeks and months still only has partial functionality or fail completely. Smart meter manufacturer wonder what the reasons are for that.

Here are the answers (PDF download):