I've been to the last 9 Glastonbury Festivals - 2002-05, 07-11 and have been lucky enough to see some of my musical heroes on a grand, magical stage, sometimes several times.
I digress. The most disappointing artist I've ever seen live is Bob Dylan at the Don Valley in Sheffield, about 8-9 years ago.
In my student days my friends and I idolised Bob. The number of times we sat around in our rocking chairs, getting monged and singing along to early Bob albums, I couldn't even come close to recounting.
Anyway when I saw him in Sheffield, he played 2 acoustic tracks all night, he played a load of obscure album tracks with heavy arrangements and his voice was absolutely awful. He sounded ill. Having had such joy with his recorded work, I was crestfallen. I remember getting the last train back across the Pennines sometimes after midnight with an empty feeling, wishing I hadn't bothered. I lost my reverence for Bob that night.
Have you ever been to a concert with high expectations, only to see them shat on from a great height?