You get those "requests" where you have to prove you are a human in order to post a message. You run into them almost every day. It's bad enough to have to prove that funny, intelligent, good-looking, flesh-and-blood you has to show that you are not a machine. But when the proof requires you to try to read blurry numbers that seem to be attached to houses that have a shady past or letters that are so wavy and squeezed together that they might as well be a pre-schooler's scribbles, it can be almost impossible. How many times have you "failed" and had to try again? And again? And again? How many times have you decided that what you wanted to say was not worth the effort of proving you are you?
Yes, spamming can be a problem. But surely there must be a better way of eliminating it than having to try to interpret indecipherable numbers and letters!