I assign myself for not knowing how to use a sphygmomanometer. I was practising on my mum the other night because she just had high BP that morning, and
the way I heard it her diastolic pressure was registering on 20! So on a related note, I assign not being able to hear anything through a stethoscope.
For something really serious, I assign suddenly hearing from high school batchmates that another batchmate just passed away, because of an autoimmune disease. He's too young...way too young...