Google's reCaptcha is easy for humans but hard for bots. It always involves clicking some button that I guess isn't detectable by bots, and then sometimes there's a pretty easy question (like I once had to identify which images had cake).
@Goerge Bobicles ,yeah, not everybody is awake at the same time, and one's night is the other's daytime. I guess me living in Europe somehow makes me able to see it happen more easily.
@andwhyisit but isn't it better if you prevent the issue instead of dealing with it?
What do you take me for? Nothing I have done has kept them out. The only thing I can suggest is that actual humans are doing the registration for the bots.
It happens in the morning for me.