It's worth noting that the editor specifically states whether the choice is small or important, even if it's conditional or preliminary. According on what you have said, it appears that they have already anticipated a possible rejection and that there is no certainty of acceptance if you make the adjustments. Therefore, it's best to send in your revised manuscript rather than attempting further revisions.
If your work obtains the verdict "accept with minor revisions," there is a good probability it will be accepted if you answer the criticisms thoroughly. Sometimes the editor or reviewers suggest changes that would improve the manuscript. In this case, you should consider their suggestions and send back your revised document. If they do not reply to your revision requests, it may be because they found no problems with the article.
Sometimes editors and reviewers request additional experiments or changes to the text for clarity purposes. For example, they may ask you to expand on a particular point or give more background information. In these cases, write back and tell them what you can do and when you can finish doing it. Usually, they will let you know how much time you have left before the publication date so that you can plan your work schedule accordingly.
If your work is accepted in its current state, contact the editor who made specific comments on your paper and express your willingness to make any necessary changes. You should also thank them for their time and effort!
In my field (chemistry), the practice is as follows: for journals that make a clear distinction between minor and major revision requests, "major revision" means that the paper will have to undergo further review after revision, usually by the same referees, whereas "minor revision" means that while changes should be made, no major changes should be made.
For journals that do not make such a distinction, authors should understand that their papers will be returned to them for major revisions if appropriate. Usually this means that the authors will have to resubmit the manuscript rather than simply making small changes themselves. However, it is possible that some journals may be willing to let authors make certain changes themselves without requesting a major revision.
The main advantage of using the term "major revision" instead of "revision" or "revise" alone is that it makes it clear that authors should not expect a fast turnaround time for their paper after submitting it. Major revisions can take months or even years to complete depending on how complex the paper is. Additionally, these revisions may require additional work by other scientists in the field, so the number of people who might be contacted by an editor to review your paper has been increased.
Finally, authors should understand that if they submit a major revision request then this will almost certainly be rejected by the journal. Such papers are typically too important for the journal to take on more work after initial submission.
When submitting an article to a journal, the verdict is generally "accept," "accept with minor alterations," "accept with substantial revisions," "reject," or "resubmit as new." The first thing to know about peer review is that it is not a judgment on the quality of your work. A manuscript may be accepted for publication even if other scientists find significant problems with its methodology or results. Rather, peer review seeks to identify errors and flaws in reasoning, so manuscripts that lack important details or evidence for their conclusions will not be published.
Peer review is done by experts who are not involved in your research project. They will not know which experiments you performed or what your findings were. They will read only your abstract or introduction, looking for information such as methodological assumptions, relevance of the study question, appropriate analysis techniques, and interpretation of results. If they feel that the paper is acceptable, then it will be sent to you for revision. You have the opportunity to respond to any concerns raised by the reviewers through written comments from you to the editor. If there are no major issues after these comments are addressed, then the paper will be sent back for final approval from the editors.
Peer review is very important for two reasons.
After extensive editing, the work may be rejected. When you submit your article after significant modification, it is allocated to the same reviewers to expedite the process. If they also reject it, that means your article was not accepted for publication.
However, if they accept it, that does not necessarily mean that it will be published. Further steps have to be taken before your article appears in print.
The editor may ask you to make further changes to the article or may request that you submit the manuscript to another journal. Often, authors are willing to change something in their article when asked to do so by the editors. For example, an author might remove a section of the text if they believe it adds nothing to the discussion and would simply slow down the review process.
If your article is accepted for publication, then it will be published in accordance with the journal's policy. This may include publishing it all at once or in stages over a period of time. Your publisher may offer additional services like peer review or research assistance for an extra charge. Some journals provide these services free of charge but others may want to recoup their costs this way. The acceptance of your article will notify you by email when it is published.
Major modifications to papers are usually sent out for review again, often to a new set of reviewers. A "revise and resubmit" with considerable adjustments is not a guarantee that your manuscript will be published, but it does indicate that you are making progress. A revised version may be accepted for publication without further review if the changes are sufficient to meet the journal's requirements.
If you do not receive feedback from the editors within six months, consider whether they were satisfied with the revisions or not. If they were not, contact them directly to ask about their decision. You have one year after acceptance into print form before your paper becomes obsolete.
At this stage, editors reject papers for one or more technical reasons: the article lacks important parts or sections needed by the journal. The manuscript subject is either outside the purpose and scope of the selected journal or is unlikely to be of interest to the publication's readership. The paper is published instead in a special issue or series that covers an area of research that has already been extensively studied or in a journal that focuses on topics related to but different from those being investigated by the authors.
Manuscripts are also rejected for non-technical reasons, such as poor writing or artwork, inappropriate length, or lack of interest from the editor. These cases are rare but do happen from time to time. If you believe your paper was rejected for non-technical reasons, discuss these issues with the editor. For example, if the journal requires original artwork or data that the author cannot provide, then this should be explained in the cover letter attached to the manuscript.
Finally, manuscripts may be rejected because they have been previously published. Publishing history can play a role in current issues journals, especially if there are substantial changes made to the paper since it was first published. In this case, the editor will usually explain what differences make the paper unsuitable for the current issue.
In all cases, reviewers will provide comments on the paper that led to its rejection.