If I'm not mistaken about the player identity( there were a few wonder kids at Flu a while back), I remember he and his father being interviewed on Brazilian TV a few years back and I was thinking how his dad was a bit too eager. I get being excited but some of these parents see the kid as a meal ticket and can only think about the check.
I don't necessarily mind Brazilian kids moving abroad young but it has to be with the right club. Extraordinary talents like Gabriel Jesus and Marquinhos are rare. There are plenty of players like Felipe Anderson and Gabriel Boschilla who are honing their skills at smaller teams who'll eventually make bigger moves.
On the other hand, if his family is extremely poor, then even a failed transfer to Europe is a success for him and his family, since he will earn a few Millions from wages and with that money his poor family is secured forever.
People probably think that he will ruin his career that way, but again, if a family and player's surroundings are very poor, then a player won't risk.
Imagine these scenarios:
1. staying at Brasil and learning more. But then, there is a risk that he will for example get a serious injury aged 19-20 in Brasil and he will never finish a transfer to Europe
2. he will jump more or less on the first opportunity to go to Europe and earn money for himself and his family.
-- if he ruins his career that way, at least he earned a few Millions
-- if he succeeds in Europe, a win-win situation
We (football fans) who are watching this from safety of our homes are only looking these footballers through glasses of what they could have achieved as footballers.
But in footballer's head, especially those from poor surroundings, there is a lot of things on their mind: football, a success in Europe, but also money, money, money, family.
For example, Gerson's wage in Roma is 1,2M Euros per yer. Even if he fails, he will get that money (and get loaned) and he will either return to Brasil or sign for some midtable Italian or European team (still probably for at least 0.3-0.5M E per year).
So, even if he fails, he will earn 5-10M Euros from Roma and from his future teams.
Quite enough for him and his family to live forever from that money.