Premine implies a system that rewards a winner but for the creator to run that system (mine) by themselves in secret before anyone else gets to (pre). It's a way to take a supposedly "fair" coin and rig it - giving most of the value to the creator. For extra shadiness they mine into many different accounts and hide the connection.
Whereas an ICO should be algorithmic. There should just be something in the rules where some number of coins are given to a creator's wallet at the start. Everyone can see it and it's a feature of the design. You can price it in.
I'm sorry but this is just propaganda from people launching new alt-coins. There is essentially no difference
In fact I've never heard of a coin that was pre-mined in a sneaky way. This term was always used to describe a coin that had pre-allocations before the genesis block. People didn't like that, so this new term "ICO" is Orwellian double speak to get people to think differently about dumping their money into a pre-mined alt-coin. It's a professional sounding word for the same thing.
One of the reasons so many people avoid and have a hard time grasping the financial industry is precisely because of the obscurification of the langauge surrounding it, and I will not participate in that charade.
Sure there's a difference. A well-publicized presale is open to anyone who wants to risk the investment. A developer'a premine only benefits the developer.
I don't really see an economic difference between putting money into a presale, and putting money into hardware and electricity for early mining.
Whereas an ICO should be algorithmic. There should just be something in the rules where some number of coins are given to a creator's wallet at the start. Everyone can see it and it's a feature of the design. You can price it in.