This lady may possible lives another 40 years. These days it is hard to get guaranteed return rate 5% every year for 40 years without WORKING on it. Most people here do not count their effort as landlord and think they have much higher return rate on rental.
For this lady's initial investment, if she passes away before run out, her beneficiary can get the remained balance. If she lives so long that run out of initial investment, she can still gets payment (insurance company may lose $$ on her but it makes money on those who dies earlier; overall, the insurance company still makes $$. For individual, it is a away to avoid longevity risk). Besides reduce the longevity risk, also keeps kids happier - The longer she lives, the more $$ she'll get.
This is NOT to promote the annuity; it is strongly suggested to visit the pros and cons of the product instead of deny it before fully understand it.