[mongol]

Yes it is part of software development in a larger sense. But there is value in it if you work as a manager. When you create your budgets you need to have an idea about how this work is split proportionally, because the work affects revenue in different ways. From a budget point of view, you can see it like: there may not be enough money to fund new feature development and the effect of that would be unfortunate. But if there also is not enough money to fund maintenance, it is worse.