For the second straight year, a robin has been incessantly flying into the windows that frame our front door every single day. He will literally fly into, and attack, our entry way several hundred times per day. It's like someone is softly knocking on our door all day long.
My wife bought these colored strips to try and distract him, but that didn't work. We put up a fake owl, and he crapped on it. We put up a bird feeder in the front yard to try and use other birds to scare him away, but he's still there.
Day after day, he just flies into my front door. I have no idea what we did to make him mad, but it's his life's mission to attack that door.