The hard part is not the ambiguous part and it never were. You just need to talk with the stakeholder to sort it out. That's the requirement phase and all it re

The hard part is not the ambiguous part and it never were. You just need to talk with the stakeholder to sort it out. That's the requirement phase and all it requires is good communication skills. The hard part is to have a consistent system that can evolve without costing too much. And the bigger the system, the harder it is to get this right. We have principles like modularity, cohesion, information hiding,... to help us on that front, but not a clear guideline on how to achieve it. That's the design phase. Once you have the two above done, coding is often quite easy. And if you have a good programming ecosystem and people that know it, it can be done quite fast.