It is said that whenever you will invest in Bitcoin,it will be the right time because Bitcoin is said to have a bright future ahead.So definitely the price will rise in future.So after sometime of your investment you will find a price better than that at which you have invested and you will be able to make profits.
I think the best time to invest in bitcoin is way back around 2014 which the price of bitcoin is totally cheap and affordable. I agree that bitcoin will have a bright future ahead so that you should invest now and do not waste your time. Once you invest in bitcoin you can assure you can gain income so that in every time you invest in bitcoin its the right time to buy and invest.
You have a point on what you are saying, and those who bought at 2014 and earlier years with a huge amount and hodl it definitely those people are now Bitcoin millionaires(Only if they Hodl) and living a life with luxury lol.
But I don't agree on what have you said that there is an assurance that you'll gain income or profit when you invested in Bitcoin because we all know that the crypto currency market is very volatile and anything can happen anytime, the price or value of Bitcoin could fly sky high or fall down in a very short period of time and no one knows if Bitcoin will still reach its price way back late 2017 and early 2018. But it still depends on the person who is investing if he/she would take the risk and invest in this speculative asset.