Task assessment and prognoses
Making prognoses are hard. There is no exception on this in IT. There are many ways and methodologies which they try to set some sort of framework up in order to do one but crucial thing: correct project / task assessments whether in terms of time or costs.
By definition, there is no person who knows the future but without trying to set some sort of deadlines and costs prognose, no business would be possible in this world. Let's take a look why it's so hard, why most advice doesn't work and what we can do about this.