Sometimes it is good investment but sometimes it is also bad.
Some ICO are real and some are not or what they called scams or fraud.

Investing in ICO is really a gamble, they might take your money and runaway or their project will make profits for your investment.

Before investing on icos do some background check about the team and also read the whitepaper.. But those fraud ICOs are doing their best to look like a real one, so it will be hard to know which is real and which is not.