Sometimes it’s the wrong rhythm, sometimes the wrong meaning
Depending on what you’ve read, you might think you should always use this comma. But there are times when it’s optional, and times when you ought not to.
This is a quick wrap-up of the most common uses for commas. It’s not likely to be of much help to you if you’re just starting out. But if you’ve already studied commas, and most particularly if you’re familiar already with some of the grammatical terms . . .