miswart

/mis·wort/, n.

[from wart by analogy with misbug] A feature that superficially appears to be a wart but has been determined to be the Right Thing. For example, in some versions of the EMACS text editor, the ‘transpose characters’ command exchanges the character under the cursor with the one before it on the screen, except when the cursor is at the end of a line, in which case the two characters before the cursor are exchanged. While this behavior is perhaps surprising, and certainly inconsistent, it has been found through extensive experimentation to be what most users want. This feature is a miswart.