By 1991 at least one competing product, DR-DOS, had introduced a well-received utility that enabled recursive file deletion.
[6] In MS-DOS, PC DOS and Windows 9x, DELTREE was implemented as an external command, with its functionality kept in a separate file outside of COMMAND.COM.
[7] Normal operation prompted the user for verification that the specified directories were indeed intended to be removed, but this safeguard could be suppressed with a command-line option.
[5] Combined with the PURGE command (which prevented data recovery), it became an example of a worst-case payload for malware[12] as well as figuring in one of the early computer sabotage trials.
[13][14] Contributing to the problem is the fact that MS-DOS and Windows 9x do not support discretionary access control to mitigate this issue.