The most common and most likely answer to this crossword clue is the 12 letter word DISADVANTAGE
I've seen this crossword clue in Independent
D
I
S
A
D
V
A
N
T
A
G
E
More clues leading to the result DISADVANTAGE
- Revised data given captures deplorable weakness
- Catch pitiful vehicle with ticket in end
- Dead against new nurses beginning to vouch for an unfavourable state of affairs
- Weakness, regrettable in singer, worried agent
- Catch Italian of 18 years stealing diamonds
- Hamper from head of department is benefit
- Navigated badly, circling wretched albatross?
Buddy explains!

The straight part
We know that "unfavourable state of affairs" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case unfavourable state of affairs = disadvantage.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 DISADVANTAGE mean?
DISADVANTAGE noun- A weakness or undesirable characteristic; a con.
- A setback or handicap.
- Loss; detriment; hindrance.
- To place at a disadvantage.