Art is such a vast subject, sometimes I almost feel slightly intimidated to give my opinion.
All art is subjective, when I mentioned my favourite painting on the other thread, Dali's "Christ of St John of the Cross" I didn't say then that I had such an immediate, almost opened mouth reaction on first seeing it. Gratifying to know therefore I wasn't alone in that reaction though as others felt the same. That was probably my first feeling of being totally moved by a piece of art, there have been other works since but never quite the same in having such an instantaneous emotion.
On the other hand, as a child we visited Malta to see extended family as that's where my paternal grandfather came from. Caravaggio lived in Malta for a while and we went to the cathedral to see his painting "The Beheading of St John" my gut reaction to that aged 11, it made me feel sick Now I can appreciate Caravaggio's work as an adult, not necessarily that one though 
I have a friend who loves Rothko's reds, and tells me she can stand in front of them and after a while becomes completely mesmerized..I'm afraid the philistine in me doesn't get that, just red canvasses
Still we're all different I guess.