Someone should&#x27;ve posted a polite correction instead of downvoting you. So:<p>The thinking behind the file system layout had nothing to do with the available disk space or having a read-only file system. It was, originally, entirely a hedge against <i>corruption</i>; before journaling file systems and all that jazz, if your system was hit by a power outage and it was in the middle of some operation or another it might corrupt whatever file system it was working in.<p>So, you would create multiple partitions and have different directories as the mount point for each partition. Say for instance that, as a cautious sysadmin, you put &#x2F;sbin on its own partition. Excellent! Since &#x2F;sbin rarely gets touched, if everything goes pear-shaped, the system will still boot into single user mode and you can use tools like fsck and mount, which are under the uncorrupted &#x2F;sbin partition and are statically linked. If you couldn&#x27;t for some reason recover the file system on a particular partition, then you might be looking at having to load, say, &#x2F;etc from backups, instead of everything under &#x2F;.<p>Over time, other software started to take advantage of multiple partition layouts to protect you from getting hurt. You could mark some partitions noexec, nosuid, or restrict operations like rm or rsync to specific partitions without having to worry about whether or not they&#x27;ll crawl out of that partition and eat the world.<p>But that&#x27;s pretty old-school now. As file systems improved and corruption was less of a problem and everybody sort of gave up caring about what options rm accepted, more and more systems just mounted everything under &#x2F; so that you would be maximally boned if ever there was a filesystem problem. Progress!<p>OpenBSD is one of few operating systems left that has a set of recommendations for how to partition your system: <a href="http:&#x2F;&#x2F;www.openbsd.org&#x2F;faq&#x2F;faq4.html#Partitioning" rel="nofollow">http:&#x2F;&#x2F;www.openbsd.org&#x2F;faq&#x2F;faq4.html#Partitioning</a><p>So that&#x27;s why I&#x27;m not a fan of &quot;novel file system layouts&quot;; the previous layout was designed and existed for some good reasons and I have a hunch that the people that are happy about novel file system layouts don&#x27;t know about those reasons.