What happens if none of the selector values match selector in a simple case expression in pl/sql

If no values in WHERE clauses match the result of the selector in the CASE clause, the sequence of statements in the ELSE clause executes. ... When the IF THEN statement has no ELSE clause and the condition is not met, PL/SQL does nothing instead raising an error.

Explanation:

okay, so i know we just goofed around in that chat, but ive been like genuinly depressed, like medically depressed for almost 4 years now. i had my first panic attack when i was 8. i woke my mum up and told her i felt like i was in a dream. like i was a goldfish in a bowl, looking at all these things going on around me and feeling . tiny. wort hless. and i now am now 17 y/o. i still feel those emotions daily. life used to go by so quick.like every day i would wake up and just like want to go back to bed cause i always felt like i was in the wrong place. i guess looking back, i was in the wrong state of mind. i took a expensive like nice trip to whyoming with my grandfather and ha ted it. like idk why. i would have loved it now, but i found myself writing in a journal everyday because i would forget what happened the day before, couldnt remember what i ate for like the previous meal. just my memory left me for the week i was there. worst feeling ive ever experienced.