I suspect many English signs in Asian countries which use incorrect grammar, including slogans on T-shirts, have had input by foreigners here being mischievous.

I suspect many English signs in Asian countries which use incorrect grammar, including slogans on T-shirts, have had input by foreigners here being mischievous. I particularly remember "No coming on the grass" as an English translation for "Don't walk on the grass" on signs in a park in China 10 years ago, and wondered if the translation had gone through some QA by a native English speaker.