Since conceptual paper doesn't have any proper structure of its own and it is addressing a question that cannot be answered properly. Then what is the relevance of that?
in a conceptual paper you try to conceptualise something new, something where there may be limited theoretical frameworks available as of yet. You can, for example, use existing theories from other fields that you transfer onto your new field in order to construct your own framework. In short, you create a concept but you do not test it.
In a research paper, however, you test concepts/models/theories by means of empirical research (either through qualitative or quantitative research, or both). The aim is to validate existing concepts. Depending on your results, this can then even lead to a revision of the concepts/theories/models you tested.
Both stages are needed and relevant to develop and continuously improve our understanding of whatever concepts/models/theories we are looking at. They form a continuous cycle where each step helps adjust the other and over again.
in a conceptual paper you try to conceptualise something new, something where there may be limited theoretical frameworks available as of yet. You can, for example, use existing theories from other fields that you transfer onto your new field in order to construct your own framework. In short, you create a concept but you do not test it.
In a research paper, however, you test concepts/models/theories by means of empirical research (either through qualitative or quantitative research, or both). The aim is to validate existing concepts. Depending on your results, this can then even lead to a revision of the concepts/theories/models you tested.
Both stages are needed and relevant to develop and continuously improve our understanding of whatever concepts/models/theories we are looking at. They form a continuous cycle where each step helps adjust the other and over again.
Conceptual papers have their own importance. They are the starting point for many ideas, models, frameworks, theories etc. They may not face the rigor of a research paper yet their significance can not be overlooked. Concept papers are good breeding ground for research.
What is the exact difference between a conceptual paper and a quantitative research paper?
Conceptual paper possibly only cover the following sections:
Research problem,
Research objective(s),
Research question(s),
Literature Review including Theories, Theoretical Framework(s) etc.
Development of the researcher's Conceptual Framework, Research Model, (some include Hypotheses)
Quantitative research paper can includes the above plus the following sections:
Research Methods - instrument developed / adopted / adapted, sampling, pilot study, data collection
Data Analyses
Results & Findings
Discusson
Conclusion (including research limitations, recommendation for future research etc.)
There might be different motivation for researcher(s) / author(s) to write conceptual paper vs quantitative research paper. Some authors prefer to split their research works & outcomes into 2 articles for publishing. The 1st article might be conceptual paper, the 2nd article might be the complete quantitative research paper. Some authors only want to write & publish as a conceptual paper because they have not completed their data collection & analysis, but yet they want the research community to know what they are doing or to solicit feedback from readers / reviewers for improvement etc.