> If a project is more than 6 months to a year in duration, there is very little chance that what the customer now wants is what they wanted before.
Depends largely on the customer. Just do anything defence, related to aircraft, or industrial control systems, more often than not, requirements are set in stone, and modifications require approval and consequent fees.
Now, those industries throw a lot of money at actual R&D to know what requirements can be requested, which is very different from your usual software shop, where "R&D" is some brief talk during refinement or at most a dedicated user story to look into the subject.
For "small" projects having requirements set in stone (probably?) works fine.
The customer might claim something different, but for a couple of large and failing projects in industrial automation I've had to fight hard to be able to iterate and rescue them from the jaws of defeat.
Depends largely on the customer. Just do anything defence, related to aircraft, or industrial control systems, more often than not, requirements are set in stone, and modifications require approval and consequent fees.
Now, those industries throw a lot of money at actual R&D to know what requirements can be requested, which is very different from your usual software shop, where "R&D" is some brief talk during refinement or at most a dedicated user story to look into the subject.