I disagree, many businesses that put their software in maintenance mode (fix/upgrade on breakage) will be losing money in the long run.

Consider a hospital, many statistics can be collected o provide insights and make immediate decisions, faster algorithms and new ones to problems we couldn't solve back then have been discovered, the UI/UX can always be improved for productivity, etc. All of that makes money.

Software customers aren't, and shouldn't be, one-time shoppers; there's always room for improvement and new needs pop up all the time.