Scenario 1: Mr A's career gets going in his 20's, but he doesn't earn enough to save. On his 30th birthday he gets a big pay increase. For the next 20 years, he earns at a rate of two houses per decade, before retiring at 50. On retirement, he actually "only" has three houses, as one house-worth of earnings was spent on general living expenses. Nevertheless, he is well off, with one house to live in and two generating retirement income from rents.
Scenario 2: Mr A marries Miss B on his 30th birthday. The trajectory of her earnings follows a roughly similar path to his, in the sense that she earns a similar amount at a similar age. She is younger than him though, so that by the time of his 50th birthday, when they divorce, they "only" have four houses between them, the three he would have had if single, and one she earned. (She has contributed nothing to joint living expenses. Given two can live together for the same cost as one alone, the house he bought to live in and the one he spent on living expenses have taken care of all their needs during the marriage.) In the divorce settlement, they each get two houses. Mr A's retirement income for his 36-year remaining life-expectancy is half what it would have been if he had remained single, as he has only one spare house to generate rent. Miss B is now earning at a similar rate to his peak, and if she works another ten years, she can expect to have three houses generating rents for her, in a retirement of similar length to Mr A's. Her disposable income will be triple Mr A's, and 50% higher than it would have been if she'd remained single all her life.
Mr A and Miss B earn the same amount over the course of their lives, but because of their age difference their high-earning years overlapped their marriage to different degrees. Consequently a 50:50 divorce settlement resulted in Mr A living one third of his life with his disposable income half what it would have been if he had never married, and Miss B living a similar period with her income 50% higher than it would have been if she'd never married.
(Does scenario 2 make sense? Could Mr A have got Miss B's future earning potential taken into account during the divorce? Would Miss B have defeated him if he tried this, for example by temporarily "retiring?")