- Investing in unknown cryptocurrencies: Just because Bitcoin has achieved success does not mean that all currencies will achieve the same success, much invested in unknown currencies for this purpose.
- Do not multiply currencies: Some people think if they have all the cryptocurrencies they will make gains, so you find them investing in more than 20 cryptocurrencies.
- Investment without a plan: You will often lose if you do not have a clear idea of what to do
The most important advice is to have a safe wallet and some technical expertise to keep your cryptocurrencies safe.
I cannot agree with you less on this position especially the first mistake which is about investing in unknown coin. Every noon trader believes by default that all coins have the potential to be like bitcoin and the time they are buying, they are actually doing it to cash out big and some exchange sites don't even help matter with the statistics they display. You see statistics such as the most traded coins, the most pumped, the most dumped, highest volume, promoted coins etc all in the last 24hrs.
However, its not possible for coins to be like bitcoin. I have fallen victim of those statistics before and I learnt the hard way that those green or red coins are really not the forces of the market but consistent manipulations of the outcome by those who knows the rule of the game.