If you're someone who loves the feel and experience of writing by hand, could you imagine losing that ability?
It happens to Parkinson's patients who develop bradykinesia, a symptom which slows movement and affects fine motor control. Writing becomes painful, leading to small, cramped handwriting, called micrographia.
That's why a group of UK university students have developed a pen specially designed to ease the writing experience for those with Parkinson's disease. (About 127,000 people in the UK have Parkinson's and about two-thirds develop micrographia.)