The other day I was trying to help someone setup a bedroom after a move and with that the topic of trying to find items such as a good pillow and mattress came up. I was then asked how long I have had mine for and I believe it actually has been over 30 years or so. The person I was speaking to thought that was crazy as technically these things have a lifespan where after so many years it is nowhere near the same as when you first got it.
I never really put much thought into it as to me it still felt comfortable and all. I guess like a sofa, if it still seems to be adequate with no major damage then why replace it? There is the argument of course where if you are using a product that isn’t performing as it should then technically you could be making things worst in the big picture. I guess it’s kind of like saying if a container you had degraded where there is this tiny opening where food won’t stay as fresh, regardless if you notice a difference you should probably replace it.
I have always been taught to use most things until they are truly out of service for the most part or it is simply uneconomical to not upgrade. Smartphones are a great example as I never saw the purpose in upgrading every year if what you have still works for what you need. A mattress is an expensive replacement too. But is tis something that you normally replace within a certain timeframe?