If your memory is anything like mine, chances are you momentarily don't remember the word "plumber". Hierarchical structures, while inflexible and sometimes pr

If your memory is anything like mine, chances are you momentarily don't remember the word "plumber". Hierarchical structures, while inflexible and sometimes prone to mis-categorization, provide navigational cues that tags don't provide. It's almost like with GUIs vs CLI - if you know what's already possible and want to express yourself precisely, you want a CLI (tags with lots of Boolean operators to precisely include/exclude). And conversely, if you don't know what's already possible, but could figure it out if you have the options laid out in front of you, then GUI (a hierarchy with all choices already laid out) will be more relevant.