Many will never invest any bitcoin in the projects because they do not want to lose. Bitcoin you want to save for the future, but Fiat is to be used for investments without any problems. It does not involve any risks.
No risks in fiat investments? You must be kidding. All investment, small or big, have risks. If there's not any, I'm sure it's some shady business or is just a scam because it's too good to be true.
People’s idea of the bitcoin has changed a lot since it was released it was supposed to be something that is going to replace the regular fiat instead people made it as an investment just like gold, and although saving might prove and get you profit but it is going to take a really dam long and I am talking like 10 years from now, so if you are not in a rush you can but if you want to make fast money you need to find a better way to invest it.
Bitcoin was only launched 7 or 8 years ago and the people that have invested back then have already made profits. Even those people that only invested last year around 600$, they have already doubled their money. 10 years is a really long time for something that exists and moves around the Internet. There's a lot of things that can happen in a day on the Internet which can change the course of bitcoin.
It will take much less time than 10 years but the longer you wait the better although it does not guarantee profit at all.