For a lot of new shops in at least western countries, writing everything in english is becoming the norm, including technical docs and comments.

The two main points I’ve seen are:

- it’s a daily pain to handle two vocabulary sets and lead to undue errors and bugs. When you have a “FishingBoat” class which related to a “boat” table and all the documentation points to “Bateau de pêche” and “barque” it’s 2x harder to follow things. Then people will accidently translate “bateau” to “ship” and it slips through a few reviews of mostly independent features, and you’ll have both words in the code base before you realize.

- it becomes a swamp the day a non native speaker touches your code base. For instance you need to share part of it with a company next door that happens to be the other side of the border. Or you ask a Romanian dev team to port your code to another platform.