Originally I began turning to ebooks more and more due to size constraints when we downsized to a smaller house after my brother married and left home.
Then as my disabilities advanced an ereader is easier on my joints, esp. on days when my hands/wrists are badly swollen/stiff. Also not having to hold my book/device directly in front of my eyes is great. I can increase font and have my device sitting on my lap or on the bed beside me while I lie/sit in a whichever position in most comfortable for me at the time.