Lloyds Banking Group interview questions

Despite weeks worth of prep having completed 4 stages of interviews sadly I wasn't offered the job. I thought it was a bit rich for them to ask me to complete a survey on the interview process seen as they offered me no feedback on any of my interviews, nor the reason as to why I wasn't offered the job. I'm now unsure where I need to strengthen and am put off applying for a position with Lloyds in the future because of this.