When will a husband's claim for maintenance be considered in the context of the wife's earning capacity?

The husband submits the wife is capable of earning income and her earning capacity should be taken into consideration in determining the amount he is to pay by way of maintenance. In Rose v. Rose, [1950] 2 All E.R. 311, at 313, Denning, L.J., dealt with this matter in the following terms: I also agree. A very important matter in awarding maintenance is the conduct of the parties. In this case it has been established that the husband broke up the marriage after twenty-one years of married life, leaving the wife with two children, one of them very young. It was a particularly bad case because the husband committed adultery with a Swiss student help who came to the house. After the divorce the wife claimed maintenance, and the question is whether she ought to go out to work. I agree that no general rule can be laid down on the matter, but this wife is certainly under no legal duty to go out to work in order to reduce the maintenance that her husband should pay. It would be quite unreasonable to expect her to do so when she has to look after a young child. If a wife does earn, then her earning must be taken into account; or if she is a young woman with no children, and obviously ought to go out to work in her own interest, but does not, then her potential earning capacity ought to be taken into account; or if she has worked regularly during the married life and might reasonably be expected to work after the divorce, her potential earnings ought to be taken into account. Except in cases such as those, however, it does not as a rule lie in the mouth of a wrongdoing husband to say that the wife ought to go out to work simply in order to relieve him from paying maintenance. I agree that the appeal must be allowed.