Worst Concerts You Have Attended ??

I just left a remark about a favorite band of mine back in the day - April Wine - that I saw in concert and was disappointed. Could have been that it was an off night for them, or maybe they were never good in concert. Maybe the lead guitarist had too much to drink? April Wine was not the worst, however. I remember Neil Young in the 1990's who was on his one-man acoustic show type of tour that many artists were taking advantage of (perhaps for financial reasons) during that time. While a friend of I had near front row seats at Desert Sky Pavilion (now Ak-Chin) in Pheonix, the crowd was just roused up into a frenzy by the warm-up band (James) and here comes Neil and his guitar/harmonica. Wow, what a sonic letdown. I remember getting up and leaving and feeling Neil's glaring eyes on us as we ushered out. I think, to this day, he probably still remembers me. We all can remember the great live concerts we attended, but what were the worst and why?
The best was probably Gram Parsons with Emmylou Harris and The Fallen Angels at Upstairs at Max’s Kansas City on March 7, 8, 9 of 1973. One night his friend Van Morrison? can’t remember if it was him or Tom Paxton, lol, was there and performed with him. I recall Neil Young and Linda Rondstat being present as well.

A friend worked the tables downstairs and she got me a front row seat (front row meant if you lean forward and rested your forearms on your knees, your head was over the front edge of the "stage") each night by letting me in through the backstage entrance before the show.
Speaking of bad concerts, am I the only one who absolutely abhors the fact that about a quarter of the crowd at any one time these days thinks it’s cool to pull out their cell phones and record for minutes on end? It takes a lot of enjoyment out of the experience to have dozens of lighted screens to look past to see a show. I’ve yet to attend an event where the no-filming rules are actually enforced. 
The Atlanta Pop Festival, July 4th & 5th 1969. The bands/music were good, but it was over 100 degrees both days. The site was the infield of Atlanta International Raceway (NASCAR) and the radiated heat off of the huge racetrack baked the crowd. Firetrucks had to be called in to spray water on many of the attendees (those they could reach) due to people passing out. It was pretty brutal because there was zero shade until the sun went down.
Gordon Lightfoot, back in the 70's. I think it was the Universal Amphitheater. The opening band was better than he was. He came out and did a half baked performance. You could tell he just wanted to get it over with  and cash his check. I never bought or watched anything he was part of again. 
Bob Dylan at Madison Square Garden in the mid-70s was pretty bad also. It was my first and what I thought would be my last stadium show. Even sitting only halfway back, between the stage and the rear, who could see or hear anything? I swore "never again" after that. But about 10 years ago I got gifted 10th row center seats to see The Eagles at MSG and the sound was perfect and while I prefer Gram to the Eagles any day, they did put on a very tight show.