Luminex interview questions

2 rounds of interview Had a call with Manager and 2nd is a team panel interview first HR calls and asks for the relative experience. The HR round is super easy and its for around 15 min

It was a 2 part interview process, the first with HR and the second with the whole team. My initial interview was due to be over the phone but I did not receive any call at the specified time. It was only when I followed up that I found out that the HR agent was having issues with her phone and assumed it was me not answering my phone? They never followed up with me so only that I called and they realised their error, I would never have had the initial interview. The interview itself was fine, standard questions. After the first interview, it was a long wait and again had to follow up before I found out I had got through to the next stage in person. Due to personal circumstances I was not able to attend and they very kindly were able to rearrange to do virtually. The interview itself again was fine with quite standard questions. I did have another job offer so I told them of this and if they could let me know if they were interested or not in offering me the position. It was only a few days later that I learned they required me to submit references before they would do a background check and it would take 2-3 weeks. I thought this was excessive especially when I did not even have a job offer but I assumed this would be a formality before a job offer would come. However in the they did not decide to offer me the job which left me quite confused, why bother doing 3 weeks of checks, leaving me wait when I had another job offer, only to not offer me the job at the end of it. Left me quite annoyed and I thought the whole process was inefficient and a waste of my time in the end.