The bug
Based on MC-80826 the /achievement
command does no longer work with statistics however the syntax and error messages are not updated.
[Client thread/INFO]: [CHAT] Unknown achievement or statistic 'test'
[Client thread/INFO]: [CHAT] Usage: /achievement <give|take> <stat_name|*> [player]
Affected translations
commands.achievement.usage
commands.achievement.unknownAchievement
commands.achievement.give.success.one
commands.achievement.take.success.one
commands.achievement.statTooLow
How to reproduce
Use the following commands
/achievement give test
/help achievement
Related issues
Comments

This was fix in 1.10, the new messages are :