Quote from "two47CTF"

I enjoy playing CTF challenges, but often found that I was not available in
the short time period that the CTF was open (usually a weekend). I also
found that often times people would unintentionally (or intentionally)
break a challenge either during or after solving it. I also don't enjoy
enumeration during a CTF, I prefer a straight forward problem to which you
need to solve. As a solution to these frustrations, I created 247CTF which
is a CTF platform that does not have an end date, nor does it have
challenge sharing between different players (each challenge instance is
unique per user), nor is significant enumeration required.