User experience designers. We are too often the lone voice for the user in teams of very smart people who think that being smart is the same as being right, working for business-minded people who are measured by production rather than quality.
We are the oracles for feature failure, and we are rarely listened to. We try to do the best we can, while refused opportunities to research, and are often brought in last minute to improve things that have already caused expensive usability and maintenance nightmares, and are blamed for being "expensive" and "out of scope" when we try to mitigate the damage.
And if an app sucks, we are the first to be blamed. But if you are a genius at your job, no one notices that you did it.