All hardware gets replaced. If your not establishing a planned maintenance schedule for your hardware then your asking for failures. That's why companies give M

All hardware gets replaced. If your not establishing a planned maintenance schedule for your hardware then your asking for failures. That's why companies give MTBF. The PLC's I have worked with have shelf life's of 30+ years , but we still have planned maintenance periods where we examine and replace and worn components and we have a tech refresh period designed to prevent anything from ever reaching a point of failure. In addition every type of media I know of to store computer programs will physically degrade before suffering "bit rot". Most of the industrial controllers I have used ( everything aside from the most basic of uControllers ) have refresh cycles for their programs preventing this supposed bit rot by refreshing the signal on the media on a very regular basis. FYI trains stations aren't torturous at all. I have put stuff on weather decks of naval warships now thats torturous.