No. of Recommendations: 5
Good article by Kitces on this topic. As we all know delaying SS mitigates against the Big Three: longevity risk, poor sequence of returns, and inflation risk. But one of the advantages for the lower-benefit spouse to claim early is in the case the higher-benefit spouse dies early. In that event, the lower-benefit spouse can still claim the higher-benefit spouse's survivor benefits. If the lower-benefit spouse dies first, the higher-benefit spouse still gets the higher claim.
There is more to it than that, but there is also some value for one spouse to claim early. Bird in the hand and all of that.
kitces.com - Why it rarely pays for both spouses to delay social security benefits 