This is very annoying for any investor as they are hoping that by getting into a project before it hits the market they are getting the best price. 83% of ICOs traded below ICO price upon being listed on an exchange.
To understand the problem we need to look at the possible causes.
Bonuses, bounties, & pre-sales: if you get a token thru one of these then you have already beat the main ICO price and your profiting selling at that price or below.
Players: because crypto is more easily accessed by anyone we have a market made up of impatient gamblers, noob investors, and many others that aren't educated in investing. While waiting for an ICO to get listed they have already found the next 3 ICOs that they want to invest in, and they will sell at whatever price they can just to get into the next one. This also indicates their bad portfolio management, because if they need to sell an ICO to get into another one right away then they are putting too much in proportion to their total bankroll. They are also easily spooked by FUD.
What can be done?
Investors don't like long lock-up periods even if it's more beneficial for them. In the case of utility tokens, they don't really need to be traded until the product is or almost is launched and the tokens can be used. At least bonuses or bounties should have a longer lock-up period stop the dumping of the seemingly “free money”.
Investors need to learn both patience, and portfolio balancing to stop dumping for the next FOMO opportunity. The most basic advice, if you have invested in a good project with a solid team, then don't sell at a price lower than you bought it at. You only officially lose the money when you sell.
It's unlikely that enough people will follow this advice to stop this from happening to at least some of your ICOs. What you do when this happens depends on your overall strategy. If you really believe in the project and are doing this as a long-term investment then either just do nothing, don't keep looking at the price until its launched its product or try to locate the bottom of its fall and buy the dip to lower your average buy price.
The above references an opinion and is for information purposes only.