It makes me think that it's worth sitting down and considering what all the valid outcomes for a piece of functionality are. A user typing in a string in the wrong format is not necessarily "exceptional", whereas running out of memory while getting the input would be. I feel like programmers too often treat perfectly valid outcomes to be errors. For example, in Rust I'll see Option<Vec<Foo>> and I ask myself if we could just use the empty vector as a valid return value.