Bug Prioritization Framework: How to Decide What to Fix First
Effective bug prioritization combines severity (technical impact) with user impact (who's affected and how badly). Use a 2x2 matrix of Severity × User Impact, automate classification where possible, and review priorities weekly. The goal: never have an engineer ask "what should I work on next?"
Your bug backlog is growing. Some bugs break critical features, others are cosmetic. Some affect your largest customer, others affect no one actively. How do you decide what to fix first?
This guide provides a complete bug prioritization framework that you can implement today—from severity definitions to scoring systems to team processes.
Why Prioritization Matters
Poor prioritization has cascading effects:
- Wrong bugs get fixed: Engineers work on cosmetic issues while critical bugs persist
- Users lose trust: Important issues go unresolved for weeks
- Team morale suffers: Constant firefighting feels chaotic
- Resources waste: Time spent on low-impact work
Good prioritization ensures your limited engineering time goes where it matters most.
The Severity × Impact Matrix
The foundation of bug prioritization is a 2×2 matrix:
textHigh User Impact │ P1: Fix Now │ P2: Fix This Week (Critical bugs │ (Major bugs affecting many) │ affecting many) │ Low Severity ─────────────┼───────────────── High Severity │ P4: Backlog │ P3: Fix This Sprint (Minor bugs │ (Critical bugs affecting few) │ affecting few) │ Low User Impact
Defining Severity
Severity measures the technical impact of the bug:
| Severity | Definition | Examples |
|---|---|---|
| Critical | System unusable, data loss, security breach | App crash, payment failure, data corruption |
| High | Major feature broken, no workaround | Can't export, search broken, auth failing |
| Medium | Feature impaired, workaround exists | Slow performance, UI glitch with refresh fix |
| Low | Minor issue, cosmetic | Typo, alignment off, color wrong |
Defining User Impact
User impact measures who's affected and how many:
| Impact | Definition | Examples |
|---|---|---|
| Critical | All users affected | Homepage down, login broken for everyone |
| High | Many users or key customers | Feature used by 50%+, enterprise client affected |
| Medium | Some users affected | Feature used by 10-50%, specific browser issue |
| Low | Few users affected | Edge case, rare configuration, single user |
Severity and impact are different dimensions. A critical-severity bug affecting one user is less urgent than a medium-severity bug affecting everyone.
Priority Levels
Combine severity and impact into actionable priorities:
P1: Critical (Fix Immediately)
- High severity + High impact
- Drop everything and fix
- All hands if needed
- Communication to users required
Response time: < 4 hours
P2: High (Fix This Week)
- High severity + Medium impact, OR
- Medium severity + High impact
- Planned for current sprint
- May require on-call attention
Response time: < 24 hours
P3: Medium (Fix This Sprint)
- Medium severity + Medium impact
- High severity + Low impact
- Scheduled in sprint planning
- Won't interrupt current work
Response time: < 1 week
P4: Low (Backlog)
- Low severity (any impact)
- Medium severity + Low impact
- Fix when convenient
- May be closed as "won't fix"
Response time: When possible
Scoring System
For more granular prioritization, use a scoring formula:
textPriority Score = (Severity × 3) + (User Impact × 2) + (Trend × 1)
Where:
- Severity: 1-4 (low to critical)
- User Impact: 1-4 (few to all users)
- Trend: 1-4 (stable to rapidly increasing)
Example Calculations
Bug A: Payment failing (Severity 4), affects 20% of users (Impact 3), stable (Trend 2)
textScore = (4 × 3) + (3 × 2) + (2 × 1) = 12 + 6 + 2 = 20
Bug B: UI misalignment (Severity 1), affects 80% of users (Impact 4), stable (Trend 2)
textScore = (1 × 3) + (4 × 2) + (2 × 1) = 3 + 8 + 2 = 13
Bug A gets priority despite affecting fewer users.
Factors to Consider
Beyond the matrix, consider these factors:
Customer Value
- Does this affect paying customers?
- Are enterprise accounts impacted?
- Is a key renewal at risk?
Weight bugs from high-value customers more heavily.
Workaround Availability
- Can users accomplish their goal another way?
- How painful is the workaround?
Bugs with no workaround get higher priority.
Reproducibility
- Can you reliably reproduce the bug?
- Is it intermittent or consistent?
Hard-to-reproduce bugs may need more investigation time.
Age of Bug
- How long has this been reported?
- Are reports increasing?
Old bugs with increasing reports deserve attention.
Fix Complexity
- Quick fix or architectural change?
- Who can fix it?
Sometimes a quick win beats a bigger priority.
Automation with AI
Manual prioritization doesn't scale. AI triage can automate:
Automatic Severity Detection
Keywords and patterns indicate severity:
- "crash", "data loss", "security" → Critical
- "can't", "broken", "failing" → High
- "slow", "sometimes", "minor" → Medium
- "typo", "color", "alignment" → Low
User Impact Estimation
AI can estimate impact by:
- Checking error rates in logs
- Counting similar past reports
- Analyzing affected user segments
Priority Assignment
Combined into automatic priority:
typescriptfunction calculatePriority(bug: Bug): Priority { const severity = classifySeverity(bug.description); const impact = estimateImpact(bug.metadata); if (severity >= 3 && impact >= 3) return 'P1'; if (severity >= 3 || impact >= 3) return 'P2'; if (severity >= 2 && impact >= 2) return 'P3'; return 'P4'; }
Team Process
Prioritization isn't just a formula—it's a process.
Daily Triage
- Review new bugs each morning
- Assign initial priority
- Escalate P1s immediately
- 15 minutes max
Weekly Review
- Review P2/P3 backlog
- Adjust priorities based on new information
- Close stale bugs
- 30 minutes with the team
Sprint Planning
- Include bug budget (e.g., 20% of sprint)
- Pull from prioritized backlog
- Balance bugs with features
Retrospective
- Which bugs took longer than expected?
- Did priority assignments hold up?
- What should we prioritize differently?
Common Mistakes
Everything Is P1
If everything is critical, nothing is. Be disciplined about true P1s—you should have very few.
Ignoring User Reports
Duplicate reports are signal. 10 users reporting the same issue means it's higher impact than you thought.
No Regular Review
Priorities change. What was P3 last month might be P1 if reports are increasing.
Skipping Low Priority Forever
P4s accumulate and create technical debt. Budget time to clear the backlog periodically.
FAQ
How to prioritize bugs effectively?
Use a Severity × User Impact matrix. Severity measures technical impact (critical to low), while user impact measures who's affected (all users to few users). Combine into priority levels (P1-P4) and review weekly. Automate initial classification with AI to save triage time.
What is bug severity vs priority?
Severity is the technical impact of the bug (how broken something is). Priority is when it should be fixed (P1 = now, P4 = backlog). A critical severity bug affecting one user might be lower priority than a medium severity bug affecting everyone.
How many priority levels should bugs have?
Four levels (P1-P4) work for most teams. Fewer levels (P1-P2) lack nuance; more levels (P1-P6) create decision paralysis. Define each level clearly with response times.
Should all bugs be fixed?
No. Some bugs aren't worth fixing: edge cases affecting no one, cosmetic issues in deprecated features, workarounds that are acceptable. It's okay to close bugs as "won't fix" with explanation.
Want automatic bug prioritization? Try BugBrain free and let AI handle initial triage so your team can focus on fixing.