Round 1 was very straight forward with hiring manager. I suspect more of a screening call than anything else. I was told on the call I would be sent a "home task". The email with details arrived later that day, but despite having all my details, they failed to set up my access to the Google Cloud repository of the sample data they wanted me to analyse. That took almost a week to resolve.
I went ahead and completed the task to a high standard. I was confident I had done it comprehensibly well enough to move through to the next round. However, sketchy feedback came back with a message that I had gone into too much detail on certain types of analysis and missed other simple analyses. There was no further information offered so I was left quite bemused to be honest.
Many people out there complain about these start-ups using candidates to get mini-projects done for free. I dismissed it at first, but now I am tending to agree with them! I spent many hours on this project, produced high quality results I believe.
I hope others manage to have a better recruitment experience with monzo than I did!