How can we quantify durability?Is it a bit confusing? The device you are using to read this post may be a couple of years old and you are thinking that it will run like this for some more time. You are not wrong and many of us do think in that way. Now, let's think of the home appliances we use daily. Some of them might be perfectly working without being repaired after the purchase and if you are asked to refer someone to a specific brand of appliance that is quite durable I am sure you will refer to the brand that is providing uninterrupted service without being repaired. You call that brand or specific model durable. The experience may vary from person to person as the other person may find the same model not so durable.
Now the interesting thing is how you are going to define durability. Is it all about the number of years it provides uninterrupted service or the period predetermined by yourself crossing which you will call it durable? For example, nowadays a mobile phone generally lasts for two to two and half years and a person will be quite satisfied if it gives uninterrupted service up to that time. The device can work well even beyond that period if it is used but if the person discards the device after that period I hope the person will rate the product as a durable one since his perception of the durability of a mobile device is two and a half years. But if a person expects that a new mobile phone will work for five years and if it starts giving trouble just after three years she/he will not consider the product durable. I have heard many commenting on hearing the passing away of an aged person by saying "he has lived enough and how long you can expect?" Again, it varies from person to person as the person making such a comment thinks that the aged person has crossed the durability while others may think the person could have lived for some more time as the person was otherwise fit, though aged.
From these examples, it may be said that the threshold of durability can vary from person to person.
This is an entry to the TOW contest