I believe it was a combination of many things. I have always thought of William as a complex character that had a development, rather than just being born a psychopath, seeing as a psychopath could not have gone in on a business with Henry. He had an abusive father (OrangeGuy)and a neglectful childhood. His father abused him both physically and emotionally due to his drinking. He thrust the same neglect on his son Michael later on. William was unstable for a long time, but the ball started rolling after Fredbear's fell on hard times. Will and Henry had limited resources and staff, far too little to support such a growing business. I believe they had to let Fazbear Ent take over the company and start calling all the shots and taking most of the profit. this shift of power made William very angry because it was supposed to be Just his and Henry's business. William's breakdown most likely caused him to drink, and he devised a plan to make the company look bad by attacking a child outside the restaurant. I'm not sure if he knew it was Henry's daughter or not, but he killed her and kept his mouth shut about it. The stress of raising a family and stress of business caused this first killing. The next string of murders was out of grief and revenge. William's youngest son getting killed by freadbear caused him to snap, and take out his aggression on a group of children at another location. He covered this, and the death of his own son up as best he could. Once he realized that the remnant from the bodies was haunting Henry's machines, he tricked Henry into helping him in his own business (Circus Baby's). At this point William was on a downward spiral into madness, designing machines that would capture children for him so he could further explore this haunting concept. He was too sloppy, and his own daughter was trapped in Baby because of his neglect. All the abuse before and after this event landed on Michael, who he felt was in some way responsible for his troubles. William's motives from here on out became revenge. Revenge on the company that caused him to lose so much. His way of getting back one last time was to kill more children at the Fnaf2 location. He did his best to cover up all of his evil deeds, but his past caught up with him. His mind had become rotted and all of his terrible actions collapsed in on him. Just like what happened after he was stuck in the springtrap suit, but on a literal level ;)
It really bothers me when someone given a high position in this well respected wiki have the balls to talk trash to others. I now that you are right, but being at your position you should represent the wiki. Even someone that has no rank knows that, its common sense. Having that position is a discgrace to this wiki. But I hope you put yourself together.
There is no standard that forces Psychobilly or any other admin to act in a certain way. So if Psychobilly feels it’s necessary to step in and say something (which she did when she felt Hotlenna was getting too nosy after invading a private conversation), then she has every right to do so.