That's because people write shitty makefiles. Most makefiles I see are full of improperly used double colon rules, phony targets not marked .PHONY and implicit ordering assumptions.
If `-j' was enabled by default, then it would be much harder for writers to develop these issues. But I suspect most of these authors, who are already unwilling to learn make properly would simply give up and use a different tool.
If `-j' was enabled by default, then it would be much harder for writers to develop these issues. But I suspect most of these authors, who are already unwilling to learn make properly would simply give up and use a different tool.