The wall usually turns up at about 30,000-40,000 words. You've written enough to have committed some serious time to the project but now you're wondering if you've made a mistake. Other ideas pitch up in your head, all of them more attractive and seductive than your boring old 30,000 or so words. The question is: should you jump ship and start again?
I think that depends on your answers to the following questions:
- Are you clear in your mind what this novel is really about? In other words, what's the underlying story you're telling eg wronged woman gets revenge, crime doesn't pay, man grows up and takes responsibility for his actions.
- Do you have an idea of where it's going? This doesn't mean you know The End, but do you have an idea of where the end might be?
- Do you have a clear idea of how your main character(s) are going to change/learn something about themselves? Novels are about change, and characters need to develop.
- Do you have a history of giving up at this point?
If you answer 'yes' to the above, then I'd say stick with it. Write down your answers in simple statements and put them somewhere so you can see them when you're writing. Then carry on writing.
If you answer 'no' to the first three, then see if you can, with some thought, come up with some answers, at which point your answers indicate you should carry on.
If you answer 'no' to the first three and can't for the life of you see what the novel you're writing is about, where on earth the ending might be, and can't see how the main character(s) are going to change then I'd give up and start again - but this time, before you commit yourself to 30,000 words, try to work out some of the answers first.
I think a lot of novelists, whether published or unpublished, come to a point where they can't stand the sight of the current work in progress and wish they'd taken up watercolour painting instead. I've done it on every novel I've written and, now I'm more experienced, just accept it as being one of those things about novel writing. Take it steadily, and write your way through the wall.