Ico is worth it to invest for me, because you purchased a coin or token before listed to the market and the price is more cheaper so that's you can get profit and if you are lucky sometimes more profit but if you unlucky your ICO you invested will failed or scam. Before investing to the project better to do some survey like askinh to the expert in ICO investing.
I think luck is a very minor contributor especially if devs intend to scam us in the first place. imo, we really can't tell until it happens. Speaking of ICOs, there's a token sale this coming July for Menlo One. Its plan is to create a scam free, user friendly, decentralized ICO marketplace. You guys should check it out
https://www.menlo.one since KoreanJew did an interview with their CEO and the project does really seem legit
https://www.youtube.com/watch?v=Rw1QBpBYE6o