Non-functional requirement

Is Non-functional requirement’s so stopper for production?

On root level yes, without non-functional requirement’s in place, any project or product (system) will not full fill requirement for end user’s.

e.g.

1: Unable to logging concurrent 10 user (Capacity, current and forecast).

2: Unreachable on and off (Accessibility).

3: Unreachable due to maintenance windows (Availability).

4: .. 

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