That's assuming users aren't resetting their locale. It's not uncommon for non english users to assume that the english version of a site is the real deal and their version is an inferior localization done by some backbenchers at whatever company made it.

For example, here's a story about how the majority of power users in Poland use an english keyboard with specialized key bindings, because using a polish keyboard marks you as a n00b: https://medium.com/medium-eng/the-curious-case-of-disappeari...

It's. Lazy. Programming.

Laziness is a virtue for programmers.

Yes. And folks have been trained to think that everyone not coding for en-us is double lazy.

There are several different ways, say a currency dropdown, that could hint on how to parse free-text input.

However, blaming the user for doing what makes sense is not helpful.

I think we're in violent agreement here - I'm trying to get across that "just use locale" doesn't necessarily mean that you're done your UI.

Even without knowing the locale, it pretty easy to know which are NoOps and which mean something.

How?

Number of digits, positioning of the , and .'s - its money which gives some nice constraints.