I'm really not sure why. There were so many reasons. Some of them weren't fully developed yet but were simmering in the back of my mind for years before I walked out. I think I left mentally at least several years before I actually threw in the towel.
There were things they taught that no longer made sense to me but that was only part of it. I was tired of bothering my neighbors on Saturday mornings with beliefs that were begining to seem old and stale. I wanted to go to the beach and enjoy nature on Saturday mornings. On Sundays I wanted to go for a run, relax and read a newspaper. Anything but to to the Kingdom Hall.
I wanted to celebrate the holidays and share in the joy others were having instead of always being a freak for what I felt was no good reason.
I could go on about haircuts, beards, reading books rather than WT publication and a zillion other things but I short I think I just felt trapped. I couldn't take it anymore and remain sane so I left and never went back. I have never regretted my decision.