And some couples, like my wife and I want more children in addition to the ones we already have. It's just we want them on our schedule. What good would a vasectomy do?
I think that there must be some couples out there with all the children they want but for some reason or the other they continue to use birth control measures. For them, it would seem to me that a vasectomy would be in order as opposed to the dangers of the “pill” or the dangers of some other birth control measure failing and whoops, a surprise!
Many years ago I worked with the husband of one of those couples. They had four children and were in their 30s but still used birth control measures thereafter. Their reasonining: they were afraid of some accident killing ALL their children (how likely is that?) and wanted to be able to start over.
I, OTOH, knew from the get-go that I didn’t want children and what better way to ensure it didn’t happen than make it impossible. Hence, the vasectomy. A little pain but 100% guarantee that it was effective.