I've known for about a

I’ve known for about a year that I would need a new workhorse in one year and I think that day has arrived. What’s strange about it is thinking about whether the planned obsolescence is mine or Apple’s. They say that 3 years is the limit for most computers, and I’ve seen this in so many cases, but how much has my own input into this computer affected its output? Did I type just one too many times on that Return key thus making the processor weary? Or was it that time I restarted four times in one day just to try out some new piece of crazy pixellation software? The question essentially boils down to nature or nurture; or, rather, technology and usage.