All cryptocurrency fundamentals are still extremely bullish, and the the long term chart is also very optimistic. As long as you stick to projects with strong background - decentralized, established team, long history and so on - you will be fine. One thing that's making investing more dangerous than anything else is the fact that people neglect their security and use centralized exchanges and closed source wallets to hold funds there. If you don't own your private keys, or can't verify the source code of your wallet to see if you are the ONLY person to access the private keys, you can make the greatest investment decision ever and later find yourself with your account zeroed. Never store your funds on centralized exchanges and only use open source wallets (Bitcoin Qt, HODLER, Electrum etc) and you'll be safe. And always look for when wallets (especially multiwallets) market market themselves to be open source but really they are closed source.