There could be several motives. He might be under the influence of drugs or alcohol, which could impair his judgment and lead to such a violent act. Another possibility is that he has some sort of personal grudge against the child or the child's family, though that would be a very extreme way to act on it. Also, if he has a history of violence or was abused himself as a child, it could contribute to his behavior.
It could be due to mental instability. Maybe he has an undiagnosed mental disorder that causes him to act out in such a violent way.
If a black man throws a child three stories, it is a very serious act. In most legal systems, this would be considered assault or attempted murder. He could face a long prison sentence, depending on the severity of the child's injuries and the laws of the jurisdiction. For example, in some places, it could be life in prison if the child dies or is permanently disabled.
This is a very disturbing situation. There could be many reasons but none of them can justify such a heinous act. It might be due to some mental illness that the man was suffering from. However, it's important to note that this act is not representative of the Muslim community as a whole, just as any individual's bad act doesn't represent their entire religious or ethnic group.
Maybe he wanted to leave some kind of evidence or confession. Or perhaps he was mentally unstable and saw it as a twisted way to make his death known.
One possible motive could be fame. People like to hear about extraordinary things, and having 1000 kids is definitely extraordinary. So, the person involved or the storyteller might be seeking attention.
Perhaps it's a sense of misguided heroism. In their mind, they see the fugitive as someone who is wrongly persecuted, and because of their love, they believe they are 'saving' the fugitive from an unjust fate. So they take the extreme step of abducting them.
It could also be for power. Some evil shinobi might believe that by capturing Naruto and somehow extracting the Nine - Tails' power, they can become extremely powerful. They might have some sort of dark jutsu or experiment in mind that requires the power of the Nine - Tails which is sealed within Naruto.
Well, it could be for shock value. People often use out - of - the - ordinary and controversial topics to make others take notice. Also, it might be a way to start a discussion about ethics, sex, and responsibility. By presenting such an extreme situation, it forces people to think about what is acceptable and unacceptable in society. Additionally, in some cases, it could be a poor attempt at creating a unique or 'edgy' story without considering the moral implications.
Maybe they believed that Hermione had some sort of special power even as a baby that could be both a danger and an asset. By kidnapping her, they could control and train her in a way that would benefit the fight against the Dark side. For example, if she was showing signs of extremely powerful magic at a young age, they may have wanted to ensure she used it for good from the start.
One possible motive could be that Sasuke has been consumed by his thirst for power. In the Naruto universe, Sasuke has often been shown to be willing to sacrifice a lot for power. In this fanfiction set in the Wave arc, perhaps he sees Sakura as an obstacle to his pursuit of power, either because she tries to stop him from following a dark path or he believes she will hold him back in some way.
It could be for a sense of self - discovery. Maybe he was exploring his limits and boundaries in a very private way.