It’s rather simple. Abusers are conscious of what they’re doing. They think if they abuse their child during the week they’re more likely to get caught because

It’s rather simple. Abusers are conscious of what they’re doing. They think if they abuse their child during the week they’re more likely to get caught because the effects of the abuse (physical and emotional) are still fresh the next day. If they do the abusing on Friday night, by Monday they think they have much less likelihood of getting caught. This may actually work a few times. But eventually they go too far.