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?
Saw Clapton in El Paso,TX while he was still in the throes of heroin addiction. Muddy Waters opened the show so it wasn't a total washout.
Diana Ross 1999 or 2000 Palace of Auburn Hills. She didn’t know the words and unfortunately her voice had seen better days.
Going way back, The Monkees @ Boston  Garden simply awfull. Hendrix was supposed to open ,but never showed up! Boy did I miss out!
Todd Rundgren in the 70s.  Hands down from this cat . . . . 

No fan.  Girfriend and her bud pleaded with me to get tickets so I did and we went.  45 minutes of mediocre, pompous pop.  45 minutes.  And despite shrieking and applauding of their fans, after 45 minutes and the last couple done by sequencers alone onstage, no encore for them.
And, since some have mentioned it, best - although like all of us there are many and perhaps tough to even consider listing, but a 70's gig by The Strawbs with backup the Welsh group Man.  Incredible.  If my recollection is right, Man was called back out for two encores with the second encore seeing members of the Strawbs off to the side of the stage.

The Strawb's Cousins later said that gig (Massey Hall, Toronto) was perhaps the best gig they ever played.