>>81689639
It's really not. The DSM and ICD constructs are just shit, surface level "negative" symptoms, i.e. what the individual lacks, instead of being "positive" symptoms, i.e. what's actually different about the person.
So naturally if you just read the diagnostics criteria and don't for example go through differential diagnoses and structured interviews like the SCID-II, you're obviously not going to get an adequate picture of the disorder. This is also why people shouldn't self-diagnose.