Some authors had a knack for story telling and could roll out books at an incredible pace.
One great example is John Creasey. Depending on the source, some say he authored over 500 books. His The Toff series alone has 59 titles. He wrote several series and wrote under multiple pen names.
I’ve read quite a few The Toff books and a few of the Baron Series. No way would I ever come close to reading all of it. Some of it is really good and other books probably shouldn’t have been published.
What other fiction writers were known for prolific writing? Try to focus on the ones that did their own writing. Writers like Brett Halliday used a lot of ghost writers to churn out books in the Mike Shayne detective series. Halliday wrote the early books and then turned it over to ghost writers.
It says a lot about Asimov that he cheated. I don’t remember the exact number, but he counts about 120 anthologies that he did little other than provide a short introduction to. The number of actual books is still amazing, but he had this dark side of needing to appear even more amazing than he was.
The majority of those 120 anthologies were from the anthology factory headed by Martin L. Greenberg. A full-time academic, he produced 1300 anthologies in all the genre fields with multiple co-editors.
That Wikipedia page doesn’t list pulp writers. Plenty of forgotten pulp writers turned out 1,000,000 words a years. Walter Gibson of The Shadow and Norvell Page of The Spider wrote 40,000 short novels every week for years. There might have dozens who worked across genres, writing for whoever was paying the most money at the time. The line goes back to the 19th century when Luis Senarens wrote 300 books, mostly in the Frank Reade series under a pseudonym.
Slumming authors churned out books by writing 10,000 words a day in their spare time. Robert Silverberg in the early 60s was a writing machine. He would write his 10,000 words - in a morning, leaving his afternoons free for his more serious fiction and nonfiction. He did lots of Ace doubles and other sf works for low-end publishers but that market wasn’t yet huge. So he wrote what is now called sleaze, soft core porn that couldn’t use dirty words or explicit scenes. At first he did one a month. The next year he did two a month. The third year he did three a month. Then he decided he needed to change his life. Andrew Offutt was a full-time insurance salesman who wanted to write full-time. To get his name known he blocked off 10-5 on Saturday and Sunday, writing his 10,000 words each day. A novel was 60,000 words then, so he finished one every three weeks, 17 a year. Similarly, when Gore Vidal needed quick money in the early 50s, he wrote mysteries. He wrote, yes, 10,000 words a day for six days, edited on Sunday, and sent the manuscript off on Monday. Those three books were published under the pseudonym Edgar Box and were pretty good, going into multiple editions before anyone learned who it really was.
If you read any article on prolific writers, let it be “O Pioneers” by James Thurber. This was the first of a five-article series on radio soap operas written for The New Yorker in 1948. Thurber profiles several of the more prolific writers, who turned out four, five, six, even seven 15-minute scripts every day for different soaps. (Subscribers to the magazine can read it in their archive. If not, it’s reprinted in The Beast in Me.) He builds as he goes along, so we get interim figures like Irna Phillips. She wrote too fast to keep up with herself so she dictated to stenographers. She managed 60,000 words a week or 3,000,000 a year. The article ends with the amazing and absolutely forgotten Robert Hardy Andrews. He averaged well over 100,000 words a week for years. In 1936 he ventured out to Hollywood to try his hand in movies. Don’t worry. He kept up by writing 27 scripts on the train. He was doing seven serials at the time but needed to cut down to four, working at the studio during the day and writing radio at night. Thurber credits him with 45 movies; IMDb has 28 listed in that time period, but it was common for writers to work on movies without final credit.
Andrews stopped writing for radio in 1942, and Thurber asked him why.