The most common and most likely answer to this crossword clue is the 11 letter word MISHANDLING
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The straight part
We know that "Bad management" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case bad management = mishandling.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 MISHANDLING mean?
MISHANDLING verb- To manipulate something roughly, causing physical damage.
- To deal with a situation incorrectly or ineffectively; to make a mistake in handling a situation.
- Incorrect handling; mismanagement.