Was a welsher – a shortcoming, indeed (9)
I believe the answer is:
defaulted
'was a welsher a' is the definition.
I can't judge whether this defines the answer.
'shortcoming indeed' is the wordplay.
I cannot really understand how this works, but
'shortcoming' could be 'fault' (I've seen this before) and 'fault' is located in the answer.
The remaining letters 'deed' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Another definition for defaulted that I've seen is " Neglected".)