The most common and most likely answer to this crossword clue is the 9 letter word CRUMPLING
I've seen this crossword clue in Financial Times
C
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M
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More clues leading to the result CRUMPLING
Buddy explains!
The straight part
We know that "failing" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case failing = crumpling.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does CRUMPLING mean?
CRUMPLING verb- To rumple; to press into wrinkles by crushing together.
- To cause to collapse.
- To become wrinkled.
- To collapse.
- The act by which something crumples.
- A crumpled shape or structure.