What are the reasons for facebook locking users' accounts ?

[Esad]

Can these reeasons be most likely cause that fb locks users' accounts?
- Virus, Spyware, Malware, Hackers, Having several accounts, Logging im more than 20 times a day?

[~o0o~]

a possibility that someone or somebody else is trying to guess your password. thus, when the attempt fails after 3times, it will lock out your account.

[Caleb]

If facebook thinks your gettting hacked they lock it so the hacker cant gain acces to your account. You can manuely lock it if your getting hacked and you do something with your phone where you can lock it and change your password from you phone. Iv had mine locked before when a kid in my class spent all day hacking it and i was stopping him so i just locked it and changed the password. I dont think viruses or any of that would cause it though, unless the virus or spyware was sent by a hacker which is likely, or the viruses job was to guess your password repetedly. I dotn think logging in 20 times would though so no on that one. and the locks ussualy last a week unless you unlock or if facebook does it you wait a week.