What makes one organization better for your writing project than another? If the new organization is clearer and easier for your readers to follow, it’s better.
The most common reason that writers update their outlines or writing plans is because as they write they figure out that a particular section will have too much information in it. Or it tackles more than one aspect of your big idea.
In other words, the original section as planned will be too hard for the reader to follow.
A benefit of having smaller, more focused sections is that you can finish them faster. The more sections of your draft you get done, the more forward momentum you have.