Why do so many drivers use mobiles whilst driving?

[QB1]

I've had 2 occasions recently when a driver (on a roundabout) was on the phone and didn't even know I was there. I didn't report them to the police .... but may be next time, I might be annoyed enough to get them prosecuted, if my life if endangered.

and you honestly reckon the Police would take any notice if you did report them?

[Snowy]

and you honestly reckon the Police would take any notice if you did report them?

I would imagine the police have to actually see them do it for any prosecution to be lawful.