Yes. Private blockchains generally run without miners and consist only of various nodes. However, public blockchains typically need miners in order to incentivize use via some type of reward, create consensus, and encourage ethical behaviors among participants.
Read moreWhy are some cryptocurrencies not mineable?
a) A lots of non mineable coins are heavily premined . They also have inferior initial coin distribution which makes a coin centralized. b) Non-mineable cryptocurrencies have generally much bigger security issues to solve because they are much more centralized in every level comparing them with the mineable coins.
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