Joseph Campbell liked to refer to "the dreamer being surprised by the dream." I think he meant the mystery of the human mind, the subconscious etc. He said something about it being ourselves who make the dream, but we surprise ourselves (or frighten ourselves) with it.
Anyway, I agree with him. I use Jungian analysis of dreams, it makes the most sense to me.
Last night I dreamt I was trying to get ready for work, but my mother hid the soap, my brother hogged the shower, my sister insisted everything was just fine, then they gave me the soap and shampoo and shower but all broken, and then all my cousins were there too, also getting ready for work, and we tried to take a taxi but there were none - etc etc etc.
The thing is that if I figure out what that dream is trying to tell me, then it will go away and not come back some day as a nightmare. I believe that absolutely, it's been true so many times.