Fanatic (UK) interview questions

1st interview was an informal chat. However, it turned into more specific questions on approach, etc. I was asked how I would improve a clients website on the fly in the interview, something I wasn't prepared for. 2nd interview was more questions as we ran out of time in the 1st round. After this, it seemed they needed to have some more examples of work, which could have been formalised as a 2nd interview with task-based examples. I ended up not pursuing further as the interview process wasn't great. Lovely people, just need to structure the interview process better and tone down the 'grilling'.