“Writing” is a broad term. Everyone specializes to an extent. Before you look at a piece and ask “does this work?”, you need to know where you want it to work. Professional, personal, or among friends? Academic or steam-punk? Novel series or flash fiction? What age is the audience? The problem is that discussions of “what works” can be completely meaningless if we do not first establish the context.
In my experience, learning to write is similar to training in a martial art. Each discipline of writing has its own flavor and even with in a particular art you can have different objectives (hobby, social, professional, practical, etc.
To help make things clearer, let’s take a couple of scenarios and see how their effectiveness changes when we change the writing context. Let’s use… a long descriptive passage. Would this work in any or every context?
In surreal fiction a fairly long descriptive passage might be necessary in order to ground the reader. In academic writing, same goes. But in flash fiction you may have just consumed half your word count with that long descriptive passage. If you are writing for very young readers, the kids may have wandered off. And if an agent or editor is reading it… they may have their doubts.
What about have use of slang? Context matters. In academic articles ya’ll prob’ly won’t ge’ away wi’ it. Young readers (who read your work themselves) also might struggle. But with right amount, right age group, and right genre… go ahead and try it.
We could go on and on.
Instead, let’s just say that defining context is essential to determining what works and what does not work. Knowing the “what works where” is important so that you – the writer – can figure out where to invest your effort. What skills to develop and what can be safely less-developed.
Even if you do write in multiple areas, I suggest that your training be 100% relevant to the contexts for which you wish to “train”. Specific training leads to specific results. Unfocused training leads to unfocused results. And unfocused results can result in missing the target agent, publisher, or audience.