In most cases, if someone notices that a person is starting to sink into addiction and tries to help him, this will have little chance of success. Because you won't be able to be with this person 24/7, and in any case, he will find an opportunity to run away or hide it from you.
Unfortunately, usually a game addict will only ask for help at the very last moment, when he is at the bottom. But there are even difficult cases when, having lost everything, they don't admit it openly. This ends very sadly for them.
Even though the chance looks small, that person should still try it, especially if the gambling addict is his best friend. No one wants to see their best friend sink into gambling and become a heavy gambling addict and they will try to save him before something worse happens to his best friend.
And if he can't be with the gambling addict 24/7, he can ask people close to the gambling addict to keep an eye on him and let him know if anything happens. But indeed, the assistance can often be too late, especially if these people cannot be with them every day and every time.