Demanding importance is reasonably elusive. It refers to someone who is exceptionally meticulous and fault-finding. A persnickety individual typically be fastidious and sets the bar high when it comes to standards and perfection. Their attention to detail can be seen as admirable, but it can also lead to unwarranted censure and unjustified dissatisfaction. Being persnickety is commonly linked to exact attention to detail but can also be seen as a manifestation of obsessiveness.

persnickety in Traditional Chinese Cambridge Dictionary