We are really not 100 % sure that our Bitcoin investment will bring profit because there's still a little bit of risk involved in Bitcoin investment whether long-term investment or short-term investment, so therefore I agree that bitcoin may not give someone the huge returns that most people expect it to actually give them.
There's high risk involve in investing in
Altcoin and should be avoided a lot of it are even scam created to manipulate people.
There is one question for you in this regard, are you talking about Bitcoin investment or investment in altcoin? Because for long term investment, it is certainly better to rely on Bitcoin and it has been proven through the value and price of Bitcoin itself since Bitcoin was created until now. You can see the Bitcoin price candle every year since Bitcoin has been in the market to find out the price level of Bitcoin that has ever happened to it every year because this year Bitcoin has also printed an all-time high price when Bitcoin was in the range of $109K and more.
As for the risk in investing, there is indeed, but every investor does not need to be too afraid of it as long as their investment goal is for the long term through Bitcoin. So making regular purchases on Bitcoin should still be considered a very good move for everyone even though they must still understand the risks. But for altcoins I can't give a picture because there are currently so many altcoins in the market that it is still necessary to select them more deeply when you want to choose them for anything.