When your teacher or editor says you're writing in poorly-developed paragraphs, do you know what they mean? After all, there's no way you can improve unless you actually understand what they're trying to tell you.
Most of the time, your problem will fall under one or more of these.
Figure it out by allotting appropriate time to reviewing your work with the help of a powerful editing software.
Your ideas are lacking.
The supporting points may be clear in your head, but unless you write it in a detailed and specific manner, it will come across as vague and abstract.
Guess what, your paragraphs will turn out undeveloped.
Provide enough detail, examples and illustration for each paragraph's main point in order to paint a clear image in the reader's mind.
As much as possible, you need to determine whether your paragraphs are poorly-developed and fix effectively.
You omitted necessary items.
Many times, a process or a flow of thought is so clear to you that you take it for granted that your reader will be of the same mind.
Guess what? They are often not.
Explain the relationships between ideas fully.
There's immense value in being thorough.
You need to define the terms you use.
During the course of your research, you will come across different terms.
Many of those will likely have different meanings depending on your reader.
You will need to clarify how you want them defined for the purposes of your piece, lest risk a potential misunderstanding.