A friend of mine just got into Bitcoin, lucky for him, his successful. Before he started Bitcoin, he was actually into a good business of selling artwork which wasn't so bad. So he got introduced to Bitcoin and had a quick success. It's actually a good and exciting thing to see someone progress fast like that, but he quit selling artworks and other little businesses that kept him going he stopped, he now depends fully on Bitcoin. Bitcoin is the king no doubt, but From my Point of view I think that depending fully on it might be risky to you financially. I don't recommend anyone to depend solely on Bitcoin or any single asset. Bitcoin can fluctuate rapidly and market volatility might impact your financial stability. It is actually very risky to invest in a single asset. The part that scares me the most is that my friend has put all his resources into this one asset. If am wrong please correct me. Thanks
A true bitcoin maxi right there 
.But I agree with you though, if your friend can keep up with the artwork business he should do it on the side, nothing wrong with having more than one source of income. Moreover, bitcoin is cyclical. If it happens that there is another bearish cycle, he can buy at the bottom forget it and distract his mind with his business.
I see that as a perfect strategy to make profit on both activity but maybe your friend is just so bullish about bitcoin
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