Hilti Group Graduate Program interview questions

I was interviewed for 2 rounds. First interview with the HR of Singapore (behavioural questions and my previous experiences) for around 30 minutes. Then, I have an informal interview with the president Lastly, I have a welding training session and assessment centre to make a presentation slides about welding product.

Interesting interview, some tough questions especially about the business model and why exactly Hilti and no competitor. Specific questions: Why do you think this Business Model is successful? What achievements are you most proud of? How would you deal with a client complaining about the product?