Any policy that restricts the number of manuscripts that can be published by a single author over any period of time seems to me to be an explicit denial of the blind peer review process. Manuscripts are not or should not be considered based on the stature, credentials, or experience of the author, but solely on the quality of the manuscript. If I were to find that a manuscript was rejected by an editor because it was a second or third submission by me in a specific period of time, I can guarantee that I would strike that journal off of my list for future submissions. I would consider the behavior of that editor to be both unethical and indefensible.
Any policy that restricts the number of manuscripts that can be published by a single author over any period of time seems to me to be an explicit denial of the blind peer review process. Manuscripts are not or should not be considered based on the stature, credentials, or experience of the author, but solely on the quality of the manuscript. If I were to find that a manuscript was rejected by an editor because it was a second or third submission by me in a specific period of time, I can guarantee that I would strike that journal off of my list for future submissions. I would consider the behavior of that editor to be both unethical and indefensible.
It is a nice question. Commonly, there is no restriction employed by most of the journals on number of manuscript submission. However, if you will submit like 5-6 journals in short period of time (5-6 months) then it will be automatically understood that quality of article is not good and journal editor will take negative effect for these.
It is important that authors be allowed to publish any number of manuscripts in the same journal as long as the quality of research is acceptable and it fits the topic of research and the objectives of the journal.