<p><br>
> This is a bit of a religious issue. Supposedly, Google did a big study<br>
> that showed that spinning idle drives down did not increase lifetime of<br>
> the drives. But other reasons for doing so might include power and heat.<br>
> Spinning down drives, assuming that they do stay spun down for a long<br>
> time and are not repeatedly spinning up and down, uses less power and<br>
> generates less heat. That is a consideration.</p>
<p>And less noise too which may be important in your living room.</p>