Indicates that the reported behavior is intentional and not subject to change.
A bug report is considered “by design” if, after review of the detailed erroneous behavior, it is determined that the behavior is desirable to keep in place rather than fix. This is independent of whether or not the behavior was known to the site developers prior to the time of the report – the important thing is that the behavior will not be altered because the current behavior is preferred.
This tag should be used only on questions reporting what is purported to be erroneous behavior and suggesting that it be fixed / reversed. For a feature request that addresses a behavior that the asker believes to be erroneous, but is intentional, status-declined should be used.
Status tags can be applied only by ♦ moderators and site developers.
Copied from: https://meta.stackexchange.com/tags/status-bydesign/info and other sites.