Egg producer initially failed to diversify (4)
I believe the answer is:
vary
'diversify' is the definition.
(varying is a kind of diversifying)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for vary that I've seen before include "Fluctuate" , "Make changes to" , "Differ, alter" , "Change according to circumstances" , "Make or become different" .)