This question is always one that recurs as new (and old) photographers explore the art more fully..
............ The real answer is "It all depends"
Many professionals shoot in jpeg.. They download their already finished image and ship it off.. no more processing necessary.
The thing to remember is that jpeg is a "lossy" format, and so if you process it over and over, and even that jpeg image out of the camera; you lose some data each time you save that re-edited image. Eventually you don't have much data left.. That may not be a bad thing if you don't ever edit more than once. Your jpeg will pretty much stay the way it is as long as you want.
So, to answer your question just as you asked it:
No, you might not get "better" edits processing in RAW first, then converting to jpeg. But what you will get is the ability to process it some; save it and look it over or have lunch, come back, reprocess it a bit more; or even go back to it next year when you get new software or want to run it through a de-noise program.. or simply reset your RAW data back to square one.
Personally, I don't usually do any processing to a jpeg file (I do save a number of finished files in TIFF though, especially if a lot of time went into the processing). Jpeg is a final conversion for the web or perhaps a disc for a friend or relative (or customer), and once it's uploaded, it gets deleted - I can always make another from the RAW image, or simply convert the finished TIFF if I ever need one..