I am currently on my third (or maybe fourth) iPhone, and every one was replaced for multiple reasons.  The headphone jacks are only good for a few thousand insertions, the batteries get worn out, the internal components start to fail, and the buttons get mushy&#x2F;broken.  In addition to this, sometimes people drop them, and the screen cracks.  The processors, ram, and solid state memory get out-of date, and make the product feel &#x27;slower&#x27; and less pleasant to use than newer devices.  In this environment, is it worth it to make spare parts and replaceable components?  Which components would you make re-usable?<p>On one corner of the desk that I am currently using, there sits an old aluminum 13.3&quot; Macbook with a replaceable battery.  I never replaced the battery because the laptop got dinged up, old, and slow, so the effort and resources that went into making the battery replaceable were wasted.  Getting rid of &#x27;serviceability&#x27; is often worth it.