I think a large population of people share this same sentiment towards Sharwarma. I might be wrong though so let me speak for myself.
I have a friend here in medical school who makes really good Sharwarma and I have helped her out with it a couple of times. But I couldn't bring myself to tasting it.
It wasn't just right in my head. She had to eventually force me to have a bite of one she recently made and it wasn't bad after all.