Once, when a man and woman got married - at least in the United States - they understood their duties fairly well. The man would support his family and the woman would take care of the household. Clear, perhaps, but not very flexible.
Then, a few decades ago, things began to change and those roles stopped being well defined. Now, if, say, the wife hates cooking and the husband loves it, then no problem, he does the cooking and nobody sneers that he is doing "women's work." And if the wife wants to work outside the home, she can do that. Nobody raises an eyebrow.
The big advantage, of course, is that the new system is very flexible, and each task can be performed by the person who enjoys it most, or who dislikes it the least.
But there is a problem with the new system.
Let's say that the wife hates ironing, but decides early in their marriage to do it for a little while as a special treat. "I just want to show how much I love him."
She doesn't see ironing as her duty, as she might have in years gone by, because now there's nothing that says ironing is one of her duties. Now she may feel that she is doing something special.
But the husband thinks, "Oh, she's more traditional than I realized. Well, I'm okay if she does the ironing."
So now she is a bit miffed. She was doing him a favor but he is taking it for granted and handing her the shirt that needs to be ironed for tomorrow's meeting. Pretty nervy!
Or, let's say she is traditionally-minded and expects that when she marries she will be able to quit her job and that her husband will provide for her to stay home and take care of the household. But he was expecting a second income. Ouch!
So, years ago the problem was lack of flexibility; now the problem is expectations. When the roles were well-defined each partner pretty much knew what to do and what the other person was supposed to do. Now not so much.
So, my unasked for advice to couples planning to get married is this: Discuss what tasks each of you will do - making sure to cover them all - then write down who will do what.
I know, I know. You don't need to write it down because you trust your spouse, but trust isn't what I'm talking about. I'm talking about memory. We forget things - especially things that we find unpleasant - so being able to refresh your minds with a written agreement can be very helpful.
I'd like to end this by saying that this is what my wife and I did before we got married. Well, we didn't. We married when the marriage relationship was still rather traditional. But in retrospect, even though things have been good for us, it might have been a wise idea all the same.