It's no surprise that as people grow older they want to continue living in their own homes as long as reasonably possible. Tthe natural process of aging tends to have an impact on ones ability to perform the simple activities of daily living (ADL).  Gradual degradations in hearing, sight, smell, and the perception of time all come to bear on living independently, and without assistance from others. All too frequently, the deciding factor in having to move a loved one into an assisted care facility is brought on by unattended cooking accidents. 

"Did I turn off the stove?" 
"That's the second pot he's burned this month." 
"She nearly burned the kitchen this time." 
"They were lucky it was only smoke damage." 
"Thank goodness the fire department got there in time."  …and so on.