Domande di colloquio per Python Backend Developer presso Flexciton

I firstly applied for optimisation engineer role on cord.co and talent acquisition partner contacted me and said they were reviewing their job requirements for that role and suggested me to apply for python backend developer role with possibility to work on optimisation so I accepted. As a foreigner I need a working visa but In their job ads it had mentioned that they were unable to sponsor visas and I raised this with talent acquisition and she said they could sponsor the visas. The interview process included 5 stages, 1- python general questions by talent acquisition partner 2- pair programming problem solving with two developers 3- oop pair programming with two developers 4-interview with lead software engineer and team lead 5- interview with CTO. I passed the technical interviews (stages 1-3) and they scheduled my interviews with team leads and CTO on the same day one in the morning other one in the afternoon. Interview with team leads was ok and I honestly explained I am interested in optimisation and in the meeting they seemed ok. But 30 mins before my interview with CTO started, they called and cancelled it and said they would reschedule it later in the same week. After 2 days, they didn’t get back to me and so that I chased up with email and they didn’t reply and on Friday they finally replied and said CTO has stepped out of recruiting process and decision was in team leads hand and unfortunately they haven’t found you strongly interested in the role. In interview with team leads, one of the guy was out of the interview half of the time because of poor connection and the other one just asked general questions. I am really curious to know how they realised I was not strongly interested? How come someone gets prepared for a five-stage tough interview conducted in 5 weeks and pass the technical interview can be not interested in the role? Isn’t the main reason that you either weren’t able or keen to offer visa sponsorship? Why do you give unreasonable feedback? Recommendation to anyone who requires visa: don’t waste your time with this company