If by successful you mean where changing one line of code takes 2 weeks of change request, 2 weeks of requirement analysis, 2 weeks of system specification tran

If by successful you mean where changing one line of code takes 2 weeks of change request, 2 weeks of requirement analysis, 2 weeks of system specification translation, 2 weeks of test specification, 2 weeks of test case implementation, 1 day of implementation and finally 2 weeks of code review, and so on. Then yes, you are completely right. In aerospace you probably want all this anyway, but for others, where 99.99% is enough, there needs to be a cheaper and more efficient way.