Some things in programming languages localise based on the $LANG environment variable. But, if you run locale -a, you will see we have less than 20 languages on Labs.
We don't even have Spanish or Chinese, which have the greatest number of native speakers on Earth.
As a project that serves more than 20 languages, we ought to install more language packs. I propose the addition of more locales in general. For starters, the remaining official languages of the UN: zh_CN, zh_TW, es_ES, and some sort of Arabic. It would be nice to have nl_NL and iw_IL as well.