I think you are not far ago register here! Because you dont know that the 90% altcoins falling to the bottom after ICO! Projects collecting millions dollars and cant support the price, is it normal?
so they sell it quickly before prices drop dramatically. Altcoin after ICO rises is very difficult so they sell after pushing it so they don't wait too long, if you wait also the results can't be bigger and there may be many other reasons why they sell fast, but I not understand for other reasons, because everyone has different thoughts.