I did OLD for five years, so I could easily fill this thread all by myself. But I will restrict myself to a few of the very worst.
As soon as he saw me arrive for our date in a cafe he pointed to my Crocs and complained "You could have worn something sexier!" I used said Crocs to walk straight out again without saying a word to him.
One youngish man came 70 miles by train to meet me for lunch, and stayed silent throughout the date. In the cab to a restaurant he stared out of the side window, ignoring me. In the restaurant he read the menu in silence, ordered, then stared silently out of the window, watching people go by. Whilst waiting for the meal and whilst eating it, every attempt I made to get him talking was shut down with "yes" or "no" answers. When he finished eating he went back to silent window staring. I was too unassertive to say anything, gave him the benefit of the doubt, telling myself he was "just shy". Soon as we finished we split the bill and I asked the waitress to call a cab. More window staring till it arrived, by which time I had given up trying to make conversation. We sat in the cab back to the station, he stared out the side window. At the station he got out, slammed the door shut and walked away without a word. He never contacted me again.
Another first date was a university tutor in robotics. We met at Charing Cross and as we walked down that side street to Embankment tube we passed a homeless man sitting in a shop doorway. This provoked my date to go on a long, angry rant against the unemployed, calling them all lazy scroungers and asserting that there was no excuse whatsoever for anyone not to get a job. I let him buy me a one-day Travelcard and we boarded a train, then I jumped out as the doors were closing and watched it pull away with him still on it. I used the Travelcard to have a ride on the entire Docklands Railway, which I had never seen before. Very angry email from him later!
Lunch date with a charming and handsome policeman who parked near my flat and texted me to say he had arrived. When I went outside to meet him he said, "Forget lunch, let's just go to your bedroom." When I declined he called me a "timewasting bitch", got in his car and drove off.
Gorgeous young guy messaged me, I mean, drop-dead handsome and a fantastic physique. Lots of photos on his profile. I fancied the pants off him before we even met. Great convo on the phone. He seemed perfect in every way AND he lived local to me. I could not believe my luck - HOW was he still single? I found out when we met - he approached me and gave me a great big grin, and that's when I found out that half his teeth were missing and the ones still present were dark brown and chipped. Ugh.