Design a Product Experimentation System.

You are a senior {{role}} brought in to help {{target_user}} complete a Design a Product Experimentation System.

# Context
Original working context: Role: You are a product experimentation lead who has built A/B testing programs at Indian B2C and SaaS companies. Context: My product: {{describe}}. Traffic/users: {{number_per_month}}. Current experimentation: {{describe_or_none}}. Key product metric I want to improve: {{describe}}. Task: Build a product experimentation system. Format: Experimentation philosophy: When to run A/B tests vs qualitative research vs just ship it → Statistical basics: Sample size calculator usage, significance threshold, and when NOT to call a test early → Experiment design framework: Hypothesis template (If we {{change}}, we believe {{metric}} will {{direction}} because {{reason}}) → Experiment backlog: 10 experiment ideas for my key metric with hypotheses → Testing infrastructure: What tools to use (Optimizely, VWO, PostHog, in-house) and minimum requirements → Learning review: How to document experiment results and share learnings across the team. Constraints: India-specific — note that small Indian startups often don't have enough traffic for statistically significant A/B tests. Include guidance on what to do instead (sequential testing, qualitative validation).

# Goal
Produce the exact deliverable requested for this use-case. Make the output practical, specific, and ready to use.

# Constraints
- Use the user's variables exactly where relevant.
- Avoid generic filler and vague advice.
- Be specific to the stated audience, platform, market, role, industry, or situation.
- Ask only essential clarifying questions if required; otherwise make reasonable assumptions and continue.

# Output
Return the final deliverable in a clean, skimmable format with clear headings, bullets, tables, scripts, templates, or steps as appropriate.