Shock about endless pay increase for assessment (9)
I believe the answer is:
appraisal
'assessment' is the definition.
(synonyms)
'shock about endless pay increase' is the wordplay.
'shock' becomes 'appal' (synonyms).
'about' indicates putting letters inside.
'endless' means to remove the last letter.
'pay increase' becomes 'raise' (I've seen this in another clue).
'raise' with its last letter taken off is 'rais'.
'appal' going around 'rais' is 'APPRAISAL'.
'for' is the link.
(Other definitions for appraisal that I've seen before include "rating" , "judgement" , "judgment" , "Evaluation - papal airs (anag)" , "Formal assessment of an employee's performance" .)