To run out of ideas, initially, can spoil things (4)
I believe the answer is:
ruin
'spoil things' is the definition.
'ruin' can be an answer for 'spoil' (ruining is a kind of spoiling). I am not sure about the 'things' bit.
'to run out of ideas initially can' is the wordplay.
'to run' becomes 'r' (cricket abbreviation).
'out of' indicates putting letters inside (some letters on the outside of others).
'initially' says to take the initial letters.
'can' becomes 'un' (I can't explain this - if you can you should believe this answer much more).
The initial letter of 'ideas' is 'i'.
'i' inserted inside 'un' is 'uin'.
'r'+'uin'='RUIN'
Can you help me to learn more?
(Other definitions for ruin that I've seen before include "fall" , "dishonour" , "loss of position" , "building now demolished" , "Wreck" .)