My view is that the single most important cause for this effect is the low cost of failing: Because software is immaterial, the cost of a fault is usually fairl

My view is that the single most important cause for this effect is the low cost of failing: Because software is immaterial, the cost of a fault is usually fairly small (in that it's rare that a bug breaks physical things), and the cost of fixing is also small. It happened to all of us: you ship a bug, someone notices it, you fix it, you ship an update, and it's done. In other engineering disciplines, failing is often life-threatening and the cost of fixing the problem can skyrocket pretty fast. So, in IT, faultlessness does not weigh very much against time-to-market or development costs. In projects were IT faults could be lifethreatening, you generally see much higher quality standards