The most common and most likely answer to this crossword clue is the 10 letter word NEGLIGENCE
I've seen this crossword clue in The Guardian
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Buddy explains!

The straight part
We know that "Failure" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case failure = negligence.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 NEGLIGENCE mean?
NEGLIGENCE noun- The state of being negligent.
- The tort whereby a duty of reasonable care was breached, causing damage: any conduct short of intentional or reckless action that falls below the legal standard for preventing unreasonable injury.
- The breach of a duty of care: the failure to exercise a standard of care that a reasonable person would have in a similar situation.