Deliveroo interview questions

Had the first 2 rounds of interviews with the HR and Hiring Manager then the position was put on hold. The position was resinstated and had 4 more rounds of interview. 1 HR, 1 Business interview, 1 case study+ analysis, and then a final round with the country head. The case study was exhaustive. had 2 data sets and a prompt. required 1 week of preparation. After going through all this, I was told that the position is no longer available as the country manager has decided to use the budget for another position. I wonder why a company of this stature had to waste 4 months of my time when they never had any intention of hiring. It was highly unprofessional and would discourage everyone from applying to this company in the Middle East region.