This is where you sell your research proposal to the reader.
You need to explain, clearly and simply, how your research will complement the field you have just described in your literature review: what you will add, how it fills an existing gap, why the academic world would benefit from your research, etc.
Many people writing research proposals make the mistake of trying to over-complicate their language with the idea that it will make them sound academic / impressive.
What is most impressive is having an idea that is worthy of academic research whilst remaining comprehensible.
Panda Tip: Please note that the nature of a research proposal will vary depending on your specific audience.
If, for example, you are addressing only academics in your precise field, you can be quite specific about your area of study and assume a high degree of existing knowledge.
This is the section that requires the most preliminary research: make sure you spend some time in an academic library and using search engines for relevant academic papers before presenting this.
You do not need to discuss every work in your area, but you need to present a competent outline, and, especially if this is a proposal for doctoral research, you need to be sure that no-one else has already done the same project.
It demonstrates that you know your field, who the key research players are in it, what has been said in the past and what is being said at the moment.
You will want to mention, and where appropriate quote from, key works in your area.