With software, many parts of the business can't "see" the development happening, so they don't know why it would take so long. At the same time, unlike a boat or building, software is more likely to be easily modified. Therefore there is less of a risk to get it all right initially. I do not condone said behavior I am merely pointing out a possible scenario in which it could happen.
It is also true that a developer is more likely to be a push over than a general contractor. Source: 11 years as as software engineer and my family has been involved with land and real estate for a long time.