The most common and most likely answer to this crossword clue is the 2 plus 3 plus 4 letter word ON THE MEND
I've seen this crossword clue in Financial Times
O
N
T
H
E
M
E
N
D
More clues leading to the result ON THE MEND
- Refusal to get up — those folk stop getting better
- Recovering, if diminished: lampoon them endlessly
- Those people joining cricket side stop improving
- Recovering, continuously swallowing them
- New parts where Riviera is improving
- Getting better, those people conclude, after operating
- Joining cricket side, those people finish getting better
- Becoming better about them getting close
- Not surprisingly, margin bound to be improving
- Getting better, working with those people on objective
Buddy explains!

The straight part
We know that "getting better" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case getting better = on the mend.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.