Top 10 operations and supply chain interview questions

An operations executive keeps the day-to-day engine running: monitoring orders or service delivery, coordinating with vendors, warehouse, delivery and support teams, solving issues before they reach customers, tracking KPIs (SLA adherence, cost per order, error rates) in daily reports, and improving processes.

Why you: connect your strengths (organisation, problem solving, comfort with data and people) to examples: "I managed logistics for our college fest: 40 vendors, a ₹6 lakh budget and a 3-day schedule. I enjoyed making a complex plan work under pressure and fixing things in real time, which is what operations is about."

Reorder point = average daily demand × lead time in days + safety stock.

Safety stock protects against variability. A simple version: (maximum daily demand × maximum lead time) − (average daily demand × average lead time). A statistical version: Z × σ(demand) × √(lead time), where Z reflects the service level (1.65 for about 95%).

Example: average demand 60/day, maximum 80/day; average lead time 5 days, maximum 7. Safety stock = 80×7 − 60×5 = 560 − 300 = 260. Reorder point = 60×5 + 260 = 560 units.

Mention that you'd review these regularly with actual demand data and adjust for seasonality.

1. Get the facts fast: where is the shipment, what caused the delay (vehicle breakdown, stock issue, address problem, weather), and what is the realistic new time?
2. Communicate proactively before the customer chases you: apologise, give the new ETA and what you're doing.
3. Solve: expedite (reassign to another rider or vehicle, ship from an alternate warehouse), or offer options (cancel with refund, compensation per policy).
4. Follow up until delivered and confirm the customer is satisfied.
5. Root cause: log the reason, look for patterns across delays, and fix the process (better carrier SLAs, buffer stock, address validation).

Map the process and measure each step's capacity, cycle time, queue length and utilisation. The bottleneck is where work piles up and utilisation is highest; it determines the whole system's output.

Then:

• Make sure the bottleneck never sits idle (no waiting for inputs, breaks staggered).
• Offload work from it (move tasks elsewhere, simplify, automate).
• Add capacity there specifically (people, equipment, shifts).
• Re-measure: the bottleneck often moves to the next constraint.

Example: a dark store where picking was fast but only one packing station existed. Orders queued at packing; adding a second station during peak hours cut dispatch time by 35%.

Define the requirement and criteria first, then compare:

• Cost: unit price plus total cost of ownership (freight, payment terms, quality failures).
• Quality: samples, certifications, rejection history.
• Reliability: on-time delivery record, capacity to scale.
• Financial stability and compliance: GST registration, legal documents, references.
• Service: responsiveness, flexibility, communication.
• Risk: location, dependence on a single supplier.

Use a weighted scorecard, run a trial order, and negotiate terms. After onboarding, review vendors monthly on KPIs (OTIF, quality rejections, price variance) and keep backup suppliers for critical items.

Warehouse: inventory accuracy, order picking accuracy, orders per labour hour, dock-to-stock time, order cycle time, fill rate, stockouts, damages, space utilisation.

Delivery: on-time delivery %, OTIF, first-attempt delivery success, average delivery time, cost per delivery, deliveries per rider per day, RTO (return to origin) rate, customer complaints/CSAT.

Explain that you'd choose a few primary KPIs tied to customer promises and cost, show them on a daily dashboard, and set targets and owners.

Lean focuses on maximising customer value by eliminating waste: overproduction, waiting, transportation, extra processing, inventory, motion, defects and unused talent. Tools include value stream mapping, 5S, kanban, poka-yoke and kaizen.

Six Sigma focuses on reducing variation and defects using data and statistics, following DMAIC: Define, Measure, Analyse, Improve, Control. The term refers to a very low defect rate (3.4 defects per million opportunities).

Many companies combine them as Lean Six Sigma: Lean makes the process fast and simple; Six Sigma makes it consistent and accurate. Give a small example if you have one, even from college projects.

STAR with numbers:

• Situation: "During my internship at a logistics startup, about 8% of shipments were returned because riders couldn't find addresses."
• Task: "I was asked to reduce failed deliveries."
• Action: "I analysed 600 failed orders and found 70% lacked a landmark or had a wrong pin code. We added landmark and pin-code validation at checkout and an automated WhatsApp message asking customers to confirm their location the day before delivery."
• Result: "Failed deliveries dropped from 8% to 3.5% in six weeks, saving about ₹1.2 lakh a month in RTO costs."

Structure matters more than the exact number:

1. Coverage: a dark store serves a radius of about 2–3 km; in a dense metro area that's roughly 1–1.5 lakh households.
2. Adoption: assume 10% of households use the app at least weekly → about 12,000 active households.
3. Frequency: 2 orders a week on average → 24,000 orders a week, about 3,400 a day.
4. Sanity check with capacity: with 15 peak hours and two peaks, a store might pick around 250–350 orders an hour at peak with 20–30 pickers and packers. So 2,000–4,000 orders a day is plausible.

State your assumptions clearly, show the maths, and sanity-check from a second angle (supply side).

"I quickly assess impact and urgency: how many customers are affected, safety or compliance risks, money at stake, and SLA deadlines. I handle safety and customer-wide issues first, delegate or escalate what others can solve, and communicate status to stakeholders so nobody is left guessing. I'd note quick fixes now and schedule root-cause fixes afterwards. For example, on a sale day when a vendor delivery failed and our dispatch system lagged, I first moved stock from another hub to keep orders flowing, escalated the system issue to tech, and updated customer support with a script for affected customers."