I don’t want to sound glib, but if you find yourself asking if you’re in development hell then the answer is probably yes. Other than that meta-remark, you can

I don’t want to sound glib, but if you find yourself asking if you’re in development hell then the answer is probably yes. Other than that meta-remark, you can take a look at how the cost and delay estimates evolve after a deadline is missed. Projects slip, but usually each missed deadline gives more visibility into the actual delivery date. If the updated budgets/plannings don’t converge, then this means the underlying project hypothèses are false (e.g. the technical complexity was completely underestimated, or the marketing target is moving faster than the project).