The author takes a specific case of iPhone development in which unit testing is difficult and generalizes it to say unit testing is not really needed. System te

The author takes a specific case of iPhone development in which unit testing is difficult and generalizes it to say unit testing is not really needed. System testing is important but it becomes hard to isolate coding errors if no unit testing is being done. I personally feel that there's a cost attached to unit testing and depending on the way the system is designed, the cost could be minimal or huge and that should be taken into account if you decide to do 100% unit testing or go for partial coverage, in no case I agree with the sentiment that it is not needed since its too hard.