The worst mistake for beginners is to rush into the market without understanding what Bitcoin is. I see no reason why one should be in haste to purchase Bitcoin without a clear understanding of what it is all about, as this will lead to nothing.
This is the same with overall investing, they've heard other people made money investing onto this 'xx' investment. And so, they hurry before they miss the opportunity that might also come to them.
But that's a huge mistake that they need to make, if they want to invest to bitcoin or any other assets. What they need to do is to make sure they have understood it beforehand.
Rushing to the waters without preparation and any other contingencies are likely to drown them. That's the same in investing if they're not going to know what they're up to before putting their money in it even it is with Bitcoin.