never change a running system

== English == === Etymology === From the field of computing, likely from German never change a running system. === Proverb === never change a running system Do not change something while it is working (because there is a risk of breaking it). ==== Usage notes ==== This proverb is primarily used by non-native speakers of English. ==== Synonyms ==== if it ain't broke, don't fix it leave well enough alone == German == === Etymology === Pseudo-anglicism, possibly from the field of computing, although this origin is disputed. === Pronunciation === === Proverb === never change a running system if it ain't broke, don't fix it; leave well enough alone === References ===