Performance is MANDATORY in this religion. You HAVE TO go door to door. If you don't then you aren't 'witnessing'.
As my Dad's dementia worsened, I watch him become despondent because he knew he couldn't do what they expected of him and he beat himself up over it.
Children are also expected to do Field Serve-Us. And what about people who are incapable due to being physically and/or mentally challenged?
And about blood transfusions, well, just hope you don't ever need one.