Contribution is not picked up then, originally (5)
I believe the answer is:
input
'contribution' is the definition.
(input means someone's contribution to something)
'is not picked up then originally' is the wordplay.
'originally' indicates taking the first letters.
The initial letters of 'is not picked up then' is 'INPUT'.
(Other definitions for input that I've seen before include "Signal supplied to a device" , "data-feed" , "Data etc supplied to computer" , "Signal feeding a circuit" , "store" .)