Bitcoin is the safest investment only among other Crypto-Currencies, because it's the currency that came first, it's the precursor of the entire market and the most trusted one by the investors. But when you think about another investments it's not safe, there isn't any guarantee you will make profit by holding Bitcoins, there is a lot of risk involved and it's very important for every investor to be aware about it before putting money on it expecting returns.
In other words, it has the first mover advantage making it the most famous cryptocurrency of all. Others even thought that bitcoin is only the coin existing because it is always the one they are hearing. When it comes to the safest investment, I think it would be bitcoin because it is the driver of the market and it has less fluctuation compared to other coins.
Many people are hoarding coins hoping that it would rise in value in the future so there would always be a demand for it. Besides that, it is used as payment option which is its real purpose and its only one of the coins that is used for its actual use case.
