[kiliancs]

In Spain, people usually have one or two names, then two last (family) names. No hyphens. In Catalonia, the two family names are sometimes "anded". Example: Miquel Martí i Pol.

[esperent]

That still fits in a form with first-<middle>-last fields. And officials reading the form will know to call the person Miquel.

First: Miquel Middle: empty Last: Martí i Pol

The problem is for names that don't work in that format.