No type checking! Declare a column as int in DDL, and
    insert a text, SQLite happily stores it without an 
    error :-(

This is the one that absolutely baffles me. They very explicitly view it as a "feature, not a bug" but I am not sure why -- I've not seen a deeper rationale behind this decision.

https://www.sqlite.org/faq.html#q3

Nonetheless though, SQLite is excellent overall and I'm so, so thankful for it.