Research is important and accurate research can be vital. You need it for anything you write. Fiction needs research just as much as nonfiction does. The reason is a writer needs to know what they are writing about. I find myself asking if something I read is true and doing a little fact checking. You can be assured if you fudge anything, some reader somewhere will call you out on it. Trust me, you do not want that to happen.
If you are writing a murder mystery and the weapon is a crossbow, you had better be able to describe it and be able to explain why your murderer would have one lying around waiting to be used to kill someone. It goes to suspension of disbelief. You wouldn’t have someone trotting around on the surface of the moon without a space suit and oxygen.
Research explains why someone would have a crossbow. Doing a little research will keep you from having your murderer shoot someone from a hundred yards away when eighty yards is the maximum range of a crossbow. Remember someone will always know what you don’t.
You don’t have to go in depth into your research. Basic research will do the job. No one will expect you to be an expert on crossbows, but you should know the basics at the very least. If killing a character with a crossbow, you should be able to describe the type of crossbow the killer used, its maximum range and the accuracy it should have at each range.
I once read a book where the main character went scuba diving on a wreck where she found the captain’s body floating in the cabin of the wreck. The implication in the story was the wreck had been there several years, if not centuries. The body would have been consumed by the denizens of the ocean, not floating. The human body doesn’t last long in aquatic environments, unless it is swimming there. I never read another book by that author – especially as she boasted she enjoyed researching her books. If she enjoyed researching her novels, it didn’t show in that book.
You don’t have to be an expert on the things you write about, but you should have a basic understanding of the subject. You can get that by doing research. Don’t be in such a hurry to publish a work that you skimp on the research. Good writing depends on what you know and you need to know it before you write about it. Take your time and do it right.
You really don’t want your readers to do the research for you. If they have to, and they are like me, they will not buy another of your books. That is not what you want to happen. A few keystrokes on the internet or a trip to the library can save you from losing readers. So, do your homework. Know what you need to know before you incorporate something in your fiction.