Not all money should be put into investment, because we should also take into consideration the worse possible scenario, and money in a bank can save us on those rainy days, even the best investors and business owners have money in the bank, part of your portfolio is having money in a bank, it's not that you will put your money to sleep but you need money that you pull out when there's a good opportunity and there's an emergency something you cannot pull out if all your money is in all your business.
And about investing, you should invest in a business where you have knowledge of how to make it profitable, never invest in a venture out of envy or because you are invited.
Of course, you cannot invest all your funds, or rather, you cannot invest everything in one asset. If you can separate your funds into different assets, then this will reduce the risks. But also, of course, you should have reserves that you do not invest, but simply keep them in an accessible place so that you can use them any time you need them.
If you know how to split your funds into different assets, then it is unlikely that they will fail at the same time. But there is another case, when at the initial stage the capital is not enough to be able to share it, and in this case it is more important not to invest all the money that you have, but to have an available reserve.
It is not necessary to keep it in the bank, since banks cannot always respond quickly, if we need your money, so some of it can be kept in a safe.