They are extremely dumb, stubborn and dirty. When they chose my balcony for their nest, they kept trying to rebuild it despite me cleaning it up several times a

They are extremely dumb, stubborn and dirty. When they chose my balcony for their nest, they kept trying to rebuild it despite me cleaning it up several times a day. Finally they laid an egg on two twigs sitting on bare concrete. They shit into their nest and their parasites (pigeon ticks) are dangerous to humans. So yes, they are bad.