I am the sort of person who likes to learn. If there is a course for the subject I am interested in, I will do it.
I've done courses galore! Fashion, Cooking, Art, Graphology, Psychology, Marketing, Business, Nursing, Law, Creative Writing, and others.
Recently I came across a very large group of writers, mostly unpublished, who really resented the idea that writing can be learnt. They believe that writing is a talent. You either have it, or you don't. They believe that it cannot be learnt, no matter what. I couldn't understand this.
I think the opposite. Sure it is always good to have some talent, but even that is a starting point. Having come late to creative writing, I really believe that writing a novel can be learnt. The "How to Write" books, the Creative Writing courses - casual and with qualification courses, writing conferences, have all taught me a great deal. But even those aren't enough.
Of course writing must be put into practice regularly. And continuous writing and dedication to getting to a goal, is necessary for improvement. When I return to what I wrote the first year, I'm embarrassed... in fact it is hard to return. Not that it was all that bad. In fact, I am often pleasantly surprised. But the style is different now - less formal, less jarred, less awkward.
However, something in those pieces of writing didn't always work. Sometimes the characters were lacking in something; the sentences were awkward; the dialogue was repetitive.
But what makes it difficult to write a full novel, is structuring. Good structure, makes a novel hang well.... as well as well drawn characters, plot and dialogue.
Whether there is talent or not to start with,
it is the Energy, Effort and Enthusiasm, and the willingness to learn from every source, that will make writing improve.