Depends! Many factors come to play and you cant say that it is imperative for any or every person to use HCG.
The need for HCG would depend on many things such as age, length of cycle, compounds used, cycle history, natural production while off cycle naturally, etc.
HCG is a great addition for most to use which helps in PCT. It is a must for me when ever I use any 19nor compounds and anything over a 12 week cycle.