You said above high standards leads to people lying and i agree with that but i'd say the equation is more like 'high standards + low tolerance for failure = people lying' high standards aren't necessarily the cause of lying, cause you can hold yourself to high standards and know you won't reach them and accept failure when you don't and move on and try again. but if you have high standards, or other people do, and the risk of failing is really high, then you're going to try to avoid failing at all costs which doesn't mean you won't but it does mean you'll try to avoid it
and in this case i don't know that i see safety and selfishness as different things and you can argue right or wrong but i think most people want to feel safe, most people want to be liked, and yeah, most people are selfish
and to be honest in my view expecting someone to tell you their whole story is kinda selfish - it puts your need to know their truth over their comfort