There has been a lot of criticism of the DSM over the years, most of it justified. Labels like "borderline personality disorder" are almost so vague as to be unhelpful.

At the same time, nobody has come up with anything better. There is so much nuance that simple labels can never capture what is really going on.

If you wanted to really accurately capture someone's personality you would need dozens of scales, 0-100, like a sadistic variant of a table-top RPG. Many of these sliders would have similar competing effects, and any test you gave would never be able to single out a single value. Then, on top of that, people actively hide and deceive the real answers to questions, and the answers might change significantly from day to day.

The key takeaway here is that you can't self diagnose or treat using labels from the DSM or (even worse) western pop psy. Practicing self awareness, finding someone you trust enough to talk honestly with, and if feasible a really good psychologist (because there are plenty of mediocre ones out there, too) is more important.