> Ahem, it's pronounced "ustedes", not "vosotros". That's not a word.

As someone who learned Spanish in Spain, I have occasionally been "corrected" by South Americans when using vosotros. Of course, no one denies that vosotros is a word, but I have been told something along the lines of "There are X Spanish-speaking countries in the world, and only one says vosotros, so please, stop doing that and talk like us instead." South Americans with this hangup are a small minority, of course, but they definitely exist.

Spanish spellings are quite standardized around the world, the “language academies” of each country collaborate together. Moreover Spanish writing is phonetic so there’s only really one way to pronounce a written word.

On the other hand, in Spain we’re famous for “cecear”, that is to pronounce “c” as the z in zombie; while in the rest of Latin America the pronounce it more like an s.

> Spanish writing is phonetic so there’s only really one way to pronounce a written word.

So there are no accents or dialects in Spain?

Of course there are. What I mean is that each letter is only pronounced one way.

For example, in English the "o" in "woman" and "women" sounds different, with exactly the same syllabic structure. However in Spanish, every time you write the "o" it is pronounced the same as every other "o". In some accents/dialects some letters will have slightly different pronunciations or intonations (e.g. c turns into s, or s at the end of a word will turn silent), but within that accent, most sounds will remain stably linked to a letter.

EDIT: Of course, I am not a linguist and I'm sure every word of my example can be debunked a million ways; but this is the experience of the language for a native Spain Spanish speaker.