My communication skills could be better
By extension of my first insight, I realized how damaging not just internal criticism is, but also criticism of others. Much of it is unnecessary or unconstructive. Then there’s the natural reaction to criticism: indignation and defensiveness. That builds up walls which impede communication. It is much better to listen attentively, and to be supportive.
And if I get to embrace my quirks, others should be entitled to theirs as well.