Khross wrote:
Taskiss:
You and I are obviously from different generations and regions than the urbanite Gladers who tell us durable goods should last 3 years.
No, but I'm an engineer and realize that you don't really understand what you are talking about. Everything is designed with a life expectancy. Typically there is a factor of safety involved, but everything is given an expiration date. This is for two key reasons: First, no engineer has the balls to say his design will last forever. Second, economics. It is not economically viable to design things to last forever. You prepare a life cycle cost estimate for maintenance and compare this to the cost of replacement. There is no justifiable reason to double the manufacturing cost of a product to increase its life expectancy 150%.
The life expectancy of a product serves the need of the consumer. Does he want the 10-year carpet or the 20-year carpet for more money? There's no right or wrong answer, it depends on the needs of the consumer.
As for lasting forever, if key items are replaced, this is feasible. However, it has to be economically viable to do so. From an engineering perspective, there is probably no reason whatsoever to keep your planes around. Furthermore, I guarantee you that your use of those planes are not "per design". I'm guessing they were intended for much heavier operation than you are currently doing. In other words, in terms of passengers or freight moved / maintenance dollar (or even time in the air / maintenance dollar since you referenced a trainer), I doubt they make economic sense at all.
So, in short - I highly doubt there is either a design intent or an economic justification to make a microwave last longer than 20 years. And since everything is designed with a life expectancy, and you don't think it should be, that's the reason for my statement that you must be frequently disappointed.