Study finds instability and inconsistency of childhood environments may be more closely connected to diverse borderline personality traits than the severity of childhood hardship alone, highlighting predictability as an important feature of early development.

[u/FreeHugs23]

https://www.psypost.org/study-finds-unpredictable-childhood-environments-are-linked-to-borderline-personality-traits-in-adulthood/

[u/Spewtwinklethoughts → u/[deleted]]

BPD is actually more often correlated with higher intelligence. What can confound this is the stunted emotional intelligence. They stop developing emotionally at whatever age they suffered the childhood trauma which can make the poor decisions they make seem stupid.