Have you ever been submitted to the following situation?
You submit a manuscript to a given magazine, sometimes you get a direct rejection (by the editor, using arguments like "this magazine receives too many manuscripts and we cannot publish all of them") or it enters in reviewing and after one month or so, you get a very nasty review, telling your work is nonsense (not to use another more colorful substantive). Then you decide you had been humiliated enough and send the same manuscript to another magazine, sometimes with a better impact factor and after some months more you receive a nice review, perhaps pointing out some mistakes you made, but finally approving the publication. What happened, wasn't the work nonsense?
Once in a joint dinner with some academic friends I placed the following question:
-"Did you ever approved a manuscript as you received?"
I meant, without asking some correction, some change, some new experiment. Of course everybody kept still.
The two problems are linked. In an ideal world, the peer who reviews your manuscript should be perfectly impartial and just. I try to be in the reviews I write (I'm not saying I achieve this goal). In fact, reviewers are humane and are subject to psychology as anyone else. The position of power over other authors sometimes is too strong to resist. The number of manuscripts increased considerably in the last 50 years and the same happened with the number of magazines. This means less prepared editors and reviewers.
What could be done? It is not possible to overload good reviewers more than what is done now, and reviewers should be trained as well. I read a proposal once in LinkedIn, the reviewers should receive a guideline, questions to be answered about the manuscript, to help performing the task. Other important thing would be that the editors take their roles more seriously. Bad reviews should not be considered in evaluating a manuscript. This means the editor should, at least, read the reviews before forwarding to the author.