How come you can't complain if you don't vote but can if you do?

They say if you don't contribute to the election then you have no right to complain about who gets elected. I can understand that reasoning, but what I can't understand is the logic that if you did vote someone in, then you do have a right to complain. You would think if you endorsed a candidate, you're partly responsible for them being in office. If you end up not liking the job they do, you have the least rights of all to complain. You made your bed, now you have to sleep in it, right? I asked two people here this question earlier today but they didn't (couldn't?) give me an answer. Sounds like a double standard to me, but I'm open to anyone willing to explain how it isn't.