hanabi

Hi all, need advice on this. My vanity cabinet with solid top was just completed by my contractor. However, there is no spacing from the edge of the left door to the wall and huge spacing from the right door to the wall as shown. When I feedback to contractor, he explained that cos it's a tight space so always will need to make smaller to fit it in, hence the gap in the right. Rubbish or truth? (p.s both sides of the wall are flushed)