Why is issuing a citation in this way so problematic? In a few places near where I live there is extremely clear signage about the speed limit, and that speed

Why is issuing a citation in this way so problematic? In a few places near where I live there is extremely clear signage about the speed limit, and that speed cameras are in effect, 100% of the time, every single day. If you speed there, you will get a ticket. The systems are configured to only send the data of speeders, and are audited. It is extremely effective. I prefer this system in every way to the way tickets are generally handled in the US. It's effective, it's fair, it does not discriminate against minorities, it does not endanger lives of the driver/police/other drivers as pulling someone over does, and it's much easier for me to avoid a ticket, it respects my privacy, persuasive / weeping / friends of cops can't get out of it, there's no chance for police to start tacking on other violations (your blinker is broken!)... etc, etc, etc. It's just better in every way, except the fact that driving on these particular roads is really boring!