Some systems glue all non surnames into a first name field and use that when just a first name would make more sense, and then in cultures where it's not usual

Some systems glue all non surnames into a first name field and use that when just a first name would make more sense, and then in cultures where it's not usual to address someone by including their middle names, a multi part name like that starts looking like a full name, which makes others assume the last middle name is the surname. I'm from a country that _has_ middle names but doesn't really use them, so I have to choose between "is this likely to be compared against official records that will need the middle name, or should I omit it so the system doesn't start referring to me as "Hi First Middle".