I take issue with the “all.” I’m positive that many, many writers never even flirted with some or most or even any of the mistakes mentioned in this brief post by Elizabeth Andre.
On the other hand, they are certainly all mistakes. Or, shall we say, tactically speaking, if you make any of these mistakes, you will never be a writer.
… yeah, pretty sure I was never really drawn to any of the enumerated mistakes.
I do remember reading a post someone wrote (sorry I can’t be more specific) about some people who say they want to be writers but they are really into worldbuilding as a hobby. And how that is a legitimate hobby as long as it’s okay with them that they never actually write a book.
I bet it’s hard to tell the worldbuilding-only hobbyist from JRR Tolkien for the first few decades of work on the world, though.