Should "feature tags" (is there a better name?) like OS (linux, osx, windows, …), license (open-source), and costs (free) only be used if they are required features?
Or may they also be used for optional features?
The question Desktop Publisher (Alternatives to InDesign) is tagged with free and open-source (which would be valid combination, as Open-Source software must not be available for free). But in the question it says:
Cost/Licence: Must be free, Ideally would be Open Source
So here free is required, while open-source is optional.
(Same case with the question Free alternatives to Matlab that run on Linux?.)
The question Free reference management software with full-text support is tagged with windows and web-apps. But in the question it says:
Target environment: Windows desktop or web
So here not both must be true (web-apps running on a Windows server; or being available cross-platform), but only 1 of 2 is required.
The question Music manager for a mass storage based music player is tagged with windows and linux. But in the question it says:
I'm running Windows 7 and 8 mainly, so I would prefer windows, but I would accept a Linux based solution if nothing else is as good.
Here the software doesn’t have to be cross-platform, it’s either Linux or Windows (or both).