Cryptocurrencies are still a new technology, which means that there is very little regulation. Especially because of the decentralization. This means that there is no governing entity which can keep you safe and guard you against scams.
I would suggest looking at the success rates of ICO promotion platforms. There are websites that offer “great” marketing plans but have no proven record of helping create successful ICO campaigns. You should avoid these websites at all costs.
On the other hand, there are platforms with a proven success rate. One example is
https://guerrillabuzz.com/ which helped their clients raise more than $100 million for their ICO’s.
Marketing plays a huge part in an ICO success. The statement “if the product is good, it will market itself” is not quite true, because it usually applies only to the top few products in a market. Famous coins like Bitcoin and Ripple can market themselves perhaps, but there are thousands of amazing products that need a little push from marketing.
Cryptocurrencies create communities. This is a fairly new phenomenon because other financial assets rarely have communities. This is where cryptocurrencies differ from stocks. There are communities centralized around them that love those coins and wish for their success. So the REAL GOAL of an ICO is to create a good community surrounding your coin. You have to gain the trust of people. This is the hardest part of a successful ICO. Platforms like GuerrillaBuzz will help you do this, in addition to creating a kick-ass marketing plan.