Let's take 2017 for example. I made more or less 700% profit on the bitcoins I bought in January and sold in December 2017. Now I am not financial expert, but I seldom see any investment opportunity where you get anything more than 30% profit within a year.
So, let's put this into perspective for the people who are constantly complaining about the price. If you were used to low interest rates or even if you were lucky enough to invest in something where you received 30% profit, ONE good year like 2017 will cover the interest and profit you would need for the next 20 years. <700% divided by the max 30%>
On top of this, you still get interest on the fiat money that you deposited into the Bank, after you sold those bitcoins.
Stop complaining and wait for your good year.
That is true. However, you should not be expecting that kind of profits on a regular basis.
There could be no pumps to the magnitude of last year's bull market rallies for years to come, and it's hard to time your investments. It's definitely not always as simple as investing in a good year and getting the profits, because you could have invested at the previous all time high and barely come out with a profit when you sell at the next bull market.
I do believe, however, that bitcoin is in a long term up trend which means that if you buy in a bear market right now and hold for the long run it is almost guaranteed that you'll make a profit. A good investment just needs to outpace inflation, and with the amount of potential new adopters in the coming years, I can see BTC easily outpacing inflation growth.
BTW, putting your money inside a bank as a long term investment just doesn't work at all. I wouldn't recommend that.