on Jane Friedman site:

I have a small confession to make: I’ve never been told I need to cut words from my manuscripts. In fact, I’m the author envious of anyone who needs to do so because I’m the one struggling to get my manuscript up to my target word count. And for a long time, I feared I was the only writer with this issue. So many writing articles and discussions focus on how to cut down an overly wordy novel to fit standard word counts, but I hadn’t seen much advice for how to bulk up a manuscript that fell below those expectations.

But over the years, I’ve found writers with similar struggles. I’m not the only one who starts with a lean first draft that needs to be built up to create a well-rounded story. Neither way of writing is right or wrong—it’s truly about what works for you and your process. The important thing is that you understand your genre’s word count expectations and why those expectations exist and that you put in the work to add or cut words to create a deep story.