If you have wondered why sites that give away free cryptocurrencies exist at all, here is the answer; Sites and apps that offer you a way to get free Ethereum make their money from advertising, and sometimes by using your CPU to help with their mining activities. They are also introducing you to cryptocurrency, in the hope that you will buy related services from them later.
There are legitimate concerns about security on Ethereum. With such a complex system, and so many different programs running on it, the attack surface is large. And given the challenges the community faces in migrating to Ethereum 2.0, including a new proof-of-stake consensus mechanism and a sharding solution for scaling transactions, it’s still not assured it will ever be ready for prime time.
Decentralizing Everything with Ethereum's Vitalik Buterin | Disrupt SF 2017
That’s not to say there aren’t risks in DeFi. Many are worried that the frenzy around speculative activities such as “yield farming” and interconnected leverage could set off a systemic crisis. If that happens, maybe Bitcoin can offer an alternative, more stable architecture for it. Either way, ideas to improve DeFi are coming all the time – whether for better system-wide data or for a more trustworthy legal framework. Out of this hurly burly, something transformative will emerge. Whether it’s dominated by Ethereum or spread across different blockchains, the end result will show more cross-protocol synergy than the chains’ warring communities would suggest.
Ripple - Bitcoin - Ethereum - EOS: Bill Gates interview How the world will change by 2030 #crypto