I own a mid-2011 21" iMac and have done so since November 2011. In that time I have used it almost every day, some days for many hours at a time, and I have restarted it twice outside of OS updates. It is always on and it is always working.
There was a blip with RAM usage which turned out to be the quite awful LogMeIn software which was close to impossible to remove, but now it is gone I am back to using my Mac without any problems every day. That surely is a problem for Apple.
Or is it?
I paid £1,000 for my iMac and could reasonably expect to be using it in 2017 which gives me roughly 6 years of use. That is £166 per year. To be fair I have added 8GB of RAM, a Microsoft mouse and the Apple extended keyboard, but asides from those, that is it.
A friend of mine recently stopped using his MacBook because it had become too slow even for his children to use to browse the internet. He has been more than impressed with the longevity and decided to buy a new MacBook which he intends to get as much use out of.
Oh sorry, my mistake, it was an 'iBook' that he has just replaced. It was used every day for 8 years and despite him not being a power user, that kind of longevity is wonderful. The only purchase during that time was a new battery half way through, and that was it.
My daughter uses an iPhone 3GS every day and it is working fine, my wife's iPhone 4 is working well and she uses it a lot. I am also sure that if I wasn't so obsessed with having the latest iPhone, my 6 would last for a good few years as well.
My point is that there is a lot of criticism levelled at Apple for the cost of new products, but for 95% of people these products represent long term investments which they can use for many years. When I compare the iMac to my recent Windows laptop experience, where HP takes little income on the product and has to fill it with crapware to make a measly profit, the difference is stark. That laptop will likely be unusable in 2 years time and the iMac will almost certainly continue to run as it does today.
This longevity means that I will replace my iMac with a new iMac one day and I will replace my iPhone with a new iPhone, and so on. In the long run I am saving money, doing productive things and Apple is also reaping the rewards. Apple isn't perfect, no company is, but my word the products are built incredibly well.