I communicated with my son's doctor through a system that included a checkbox with label Not Urgent that defaulted to checked. As I submitted an urgent message, I clicked that checkbox and hit submit in quick succession.

Later I went through sent messages and the urgency indicator was opposite of intended on all. I looked at the form more closely and realized that the label was actually indicating what clicking the checkbox would change the state to, so clicking indicated it was not urgent.

I emailed the company about the confusing behavior and received no response.