Many subjects, such as using certain tools and programming languages, promote objective answers: "How do I do this?" returns answers such as "Do A, B and C".
However, certain subject areas, such as architecture and design promote more subjective answers. Questions in these areas are often worded more like "How would you approach this?" or "What is the common way to solve this problem?", and these return subjective answers like "I would do it like this..." and "I disagree with X, I would do it this way...".
People are often very quick to critisise these subjective answers, but that is the nature of software design and architecture.
So if subjective answers are not allowed on SO, should we even have tags like 'architecture', 'software-design', 'soa' et cetera that promote subjective answers?