Stress
A lot rests on your shoulders and you have a difficult, time- and brain-consuming job to do. If there are inaccuracies in your research, if you fail to grow an adequate collection to represent a certain period or species, or if a T-rex skeleton suddenly comes alive and starts eating the other fossils, that’s all on you.
Most curators, however, have plenty of chances to travel (doing work-related research) and continue to learn in many and varied ways about their particular area of expertise, so at least it isn't boring. Come to think of it, you've been meaning to get away for a relaxing weekend in the Peruvian Amazon. So…yeah. It's a low- or no-stress job. If you really screw things up, will people really even notice?