Property investment is a little different because you can usually recoup at least some of the money spent at a later date by selling the property. A building without a wood rot problem will always be worth more than one with one, especially when the problem is likely to get worse over time if it's not dealt with.

A software project on the other hand is typically worth close to nothing if it doesn't fulfil it's requirements , so the sunk costs are different.

To the second point, the problem with programming projects is that you are often competing against more enthusiastic and less experienced devs who are naive and under estimate.