The most common and most likely answer to this crossword clue is the 4 plus 6 letter word LOST CAUSES
I've seen this crossword clue in Independent
L
O
S
T
C
A
U
S
E
S
More clues leading to the result LOST CAUSES
- Vagrant outclasses no-hopers
- Whizz outclasses those without hope of success
- Disorganised scout sales are hopeless affairs
- Misplaced grounds or reasons for 3?
- Fruitless campaigns, having mislaid bags outside university
- Gone cases! You may go into them but they have no chances of coming back
- Hopeless situations when cassoulet’s prepared
- No-hopers mislaid baggage containing uniform
- Hopeless situations when cassoulet's prepared
Buddy explains!

The straight part
We know that "hopeless affairs" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case hopeless affairs = lost causes.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.