I don't know how long it takes to become a good writer.
All I know is that back in 2002 I almost failed high school because I was such a bad writer.
And after I graduated back in 2004 I didn't write anything for another 9 years.
I think during those 9 years I even forgot the alphabet.
And when I started my blog back in the summer of 2013 I had no clue about writing and had maybe read a total of 10 books in my entire life.
So how long does it take to become a good writer?
I really don't know.
All I know is that I forgot the alphabet and now you're reading this right here...