Non-functional requirements (NFRs) define the quality characteristics that a system must exhibit — how fast, how available, how secure, how scalable, and how recoverable it must be — independently of the functional capabilities it delivers. Where functional requirements describe what a system does (produces a consolidated balance sheet, runs a planning workflow), NFRs describe how the system must behave while doing it (produces the consolidated balance sheet in under 30 seconds for 50 concurrent users, with 99.5% uptime during business hours). NFRs are not afterthoughts; they are design constraints that directly determine infrastructure sizing, architecture decisions, and the acceptability of vendor platform choices.
NFR Categories for ERP and EPM Programmes
| Category | Key Questions | Measurement Basis |
|---|---|---|
| Performance | What is the acceptable response time for high-volume operations? What is the maximum consolidation run duration? How many concurrent users must the system support? | Response time in seconds; concurrent user count; batch job completion time |
| Availability | What are the required uptime hours? Is the system needed 24/7 or business hours only? What maintenance windows are acceptable? | Uptime percentage; maximum planned downtime per month |
| Scalability | What entity or dimension growth is expected over three to five years? Can the platform scale without architectural change? | Entity count; data volume; user count — projected at horizon years |
| Security | What data classification applies? What access control model is required? What encryption standards must be met? What regulatory compliance applies (ZATCA, SAMA, PDPL)? | Compliance standard adherence; access review frequency; encryption protocol |
| Recoverability | What is the maximum acceptable data loss (RPO)? What is the maximum acceptable recovery time (RTO)? | Recovery Point Objective in hours; Recovery Time Objective in hours |
| Maintainability | Can the system be maintained by the client team without vendor dependency? What is the expected patching and upgrade cadence? | Skill requirement for maintenance; upgrade effort in person-days |
Common Gaps and Failure Modes
The specific failure that most consistently produces post-go-live performance problems is NFRs defined at a category level without specific, measurable thresholds: “the system must perform adequately” rather than “the planning consolidation run must complete within 45 minutes for 200 entities at full data volume.” Without specific thresholds, performance testing has no pass/fail criterion, the vendor has no obligation to remediate, and the client discovers the actual performance characteristic on the first live close cycle — when the consolidation run takes three hours and the finance team cannot complete the close on time. NFRs must be measurable to be enforceable.
How Loop Wise Solutions Produces This
Loop Wise Solutions elicits NFRs in a dedicated workshop with the client’s finance, IT, and IT security teams — using a structured NFR template that prompts for specific, measurable thresholds in each category. Where the client does not know what thresholds are appropriate, we provide benchmark guidance from comparable implementations. The finalised NFR document is incorporated into the solution design document and into the performance testing plan, providing the measurable criteria against which the system is accepted before go-live.
