Here are some of those concrete, nitty-gritty tips I mentioned, in the form of reasons why applications fails.
Taking on too much for a sole investigator over the allocated time period.
A mismatch between the proposed research and the candidate’s attested academic background.
Failing to state the aims up front and explicitly.
Failure to explain in accessible terms why the research matters: to one’s discipline and more broadly.
Not making clear enough what the applicant’s own original contribution will be.
Describing how the funds will be spent, but not explaining why such spending is necessary for the success of the research project.
Ignoring the funding agency’s instructions, criteria and section headings.
Writing as if the application were a book prospectus or an academic essay.
Not considering carefully enough the various readerships of the application, and which sections will be read by whom.
Failure to integrate the stated objectives with the proposed methodology, and then with the plans for communication of results.