This is complicated.
I largely agree with you that waiting to take social security generally doesn’t make since. In my case (because I know the numbers), I will have forfeited $129,000 in the years between 62 and 67 by waiting until I’m 67 to take social security (SS). And I don’t break even on that until I’m 77. (If I waited until I’m 70 to take social security, I will have forfeited $211,000 and I wouldn’t make that up until 79. There are many, many variations (66 to 70 etc.) that I won’t go into. But we can all agree, there is a breakeven point where waiting would make the most sense. And if we all knew that we’d be skiing and hang gliding at age 100, we’d wait until 70.
So let’s look into the spouse issue. Say I take SS at 62 and I die at 67. You’d say “it’s great that you took it early, you got that $129,000 that you wouldn’t have received if you’d waited.” But my wife is 11 years younger than I am, and she didn’t work as long as I did. Because of that, using my social security benefit is her best option when her times comes. She can either take 70% of my benefit at age 60, or 100% of my benefit at age 66. For comparison the best and worst case scenarios in this example are as follows:
$25,000 @ 70% = $17,500 at age 60 using my age 62 benefit
$50,000 @ 100% = $50,000 at age 66 using my age 70 benefit
That’s quite a swing, especially if my wife lives for another 30 to 35 years.
No matter how you look at it, my decision in the scenario above will affect her amount. So we will in essence be using my social security though my life expectancy, and then using my social security through her life expectancy. Because of that compounding of our life expectancies if you will, we will both live though that breakeven point where waiting makes sense.
As I started this discussion, if I was single and not working after 62, it would be a no brainer to take SS at 62. Or if I was married to a person who’s SS was comparable to mine I’d still take it at 62. But if I believe that my wife’s best option will be take use my benefit when I die and she will live at least into her early 70s, it makes sense to wait on SS for her benefit.