Obviously, in hindsight, it would have been best to enter 8 years ago with Bitcoin. But there's still so much potential (in terms of tech & price) for cryptocurrencies in general, so now is fine too. 
Yep, 8 years ago was the ideal time for bitcoin. But now you hardly can make a good profit with bitcoin. Alas, it's too late. However, there is a world of alternative crypto-currencies that are not too late to use to exaggerate your funds. I consider now is the most suitable time for this