the chemical composition of cilantro can be very... floral for lack of a better term. for some it can come off as tasting like soap. scienctist actually is during research to determine why. one idea is that its got to do with our genetics. certain parts of the world use loads of cilantro while others use none. so you may be prediposed to hate the stuff and get the soapy taste.
cilantro taste like soap to me, but a little of it in the right dish, taste yummy to me.